Gemstone & Mineral Guide

This chart shows different stone details with descriptions.

S. N.	Names	Family	Color	Moh's Hardness	Density	Transparency	Occurance	Country of Origin	Chemical Composition	Short Description
1	AEGIRINE	clinopyroxene group of inosilicates	Dark Green, Greenish Black	6	3.5 to 3.54	Transparent	Common	Norway,Buskerud,Kongsberg	pyroxene group	Aegirine is the sodium endmember of the aegirine-augite series. Aegirine occurs as dark green monoclinic prismatic crystals. It has a glassy luster and perfect cleavage.
2	ADAMITE	Olivenite	Yellow	3.5	4.32 - 4.48	Translucent	Common	Mexico	Zinc Arsenic Hyroxide	Adamite is a zinc arsenate hydroxide mineral, Zn2AsO4OH. It is a mineral that typically occurs in the oxidized or weathered zone above zinc ore occurrences. Pure adamite is colorless.
3	ADULARIA									Another name for Orthoclase. Please see Orthoclase
4	AGATE	Chalcedony	White, grey, green, yellow, brown	6½ - 7	2.58 - 2.64	Opaque	Very Common	Angola, Armenia, Bulgaria, India, Jamaica, Panama, Papua New Guinea	Silicon Dioxide	Agate is a microcrystalline variety of quartz, chiefly chalcedony, characterized by its fineness of grain and brightness of color. Although agates may be found in various kinds of rock, they are classically associated with volcanic rocks but can be common in certain metamorphic rocks.
5	AGATE W/ AMETHYST									Please see Agate & Amethyst
6	AGUA NEVADA
7	ALABASTER	Gypsum	White, pink, brown	2	2.32	Translucent to Opaque	Common	Italy	Hydrated Calcium Sulfate	Alabaster is a substance is sulphate of lime or gypsum. Alabaster is a fine-grained variety of gypsum. It is one of the softest minerals known to nature and It is widely used as an ornamental stone in sculpture.
8	ALABANDITE	Galena group	Iron black,brown,green, green	3.5 to 4	3.95 - 4.04	opaque		Aydin in turkey, Alabanda	Manganese sulfide	Group of octahedral alabandite crystals partially coated with pink rhodochrosite.
9	ALBITE	Feldspar	White, blue, grey	6 - 6½	2.6 - 2.65	Transparent to Translucent	Common	Angola, Antarctica, Argentina, Armenia, Tunisia, Thailand, Turkey	Sodium Aluminum Silicate	Albite is a common felspar and is the "pivot" mineral of two different feldspar series. It is most often associated with the plagioclase series where it is an end member of this series.
10	ALBITE JADE									Please see Albite & Jade
11	ALEXANDRITE	Chrysoberyl	dark red, yellow-red, dark green, orange-yellow	8½	3.64 - 3.68	Transparent to Translucent	Uncommon	Sri Lanka, India, Mongolia, Paraguay, Slovakia, Ukraine, Uruguay, Yemen	Beryllium Aluminum Oxide	The alexandrite variety displays a color change dependent upon light, along with strong pleochroism. Alexandrite results from small scale replacement of aluminum by chromium oxide, which is responsible for alexandrite's characteristic green to red color change.
12	ALMANDINE	Garnet	Red with violet tint	7 - 7½	3.93 - 4.30	Translucent	Common	Afghanistan, Algeria, Brazil, Burma , Colombia, Guatemala, Nepal	Iron Aluminum Silicate	Almandine, also known incorrectly as almandite, is a species of mineral belonging to the garnet Group. Almandine is an iron alumina garnet, of deep red color, inclining to purple.
13	ALLOPHANE	Kaolinite-serpentine	White,green, blue	3	1.9	Translucent		grafenthal,germany	Hydrous Aluminium silicate clay mineraloid	Allophane is a weathering or hydrothermal alteration product of volcanic glass and feldspars and sometimes has a composition similar to kaolinite but generally has a molar ratio of Al:Si = 2. It typically forms under mildly acidic to neutral pH (5-7).
14	ALUMINUM	Metal	Bright grey, silver	1½	2.7	Opaque	Common	Azerbaijan, China, Italy, Russia	Aluminum Oxide	Aluminum is a soft, durable, lightweight, malleable metal with appearance ranging from silvery to dull grey, depending on the surface roughness. Aluminum is nonmagnetic and nonsparking.
15	ALUNITE	Alunite	White, yellow- grey	3½ - 4	2.6 - 2.9	Translucent	Uncommon	Bulgaria, Canada, Chile, China, Eritrea, Egypt, Fiji, Ecuador, France, Philippines	Hydrous Potassium Aluminum Sulfate	Alunite is also known as alumstone and is a source of the chemical known as alum. Alunite forms from the action of sulfuric acids upon potassium rich feldspars in a process called "alunitization".
16	AMAZONITE	Feldspar Microcline	Green, blue-green, light green	6 - 6½	2.56 - 2.58	Opaque	Uncommon	Burma, Portugal, Madagascar, Russia, Zimbabwe, South Africa,	Potassium Aluminum Silicate	Amazonite is a green variety of microcline feldspar. The name is taken from that of the Amazon River, from which certain green stones were formerly obtained, but it is doubtful whether green feldspar occurs in the Amazon area.
17	AMBER	Organic Amber	Yellow, brown, orange-red	2 - 2½	1.05 - 1.09	Transparent to Translucent	Common	Israel, Germany, Japan, Lebanon, Lithuania, Malaysia	Succinic Acid	Amber is fossil tree resin, which is appreciated for its color and beauty. Although not mineralized, it is often classified as a gemstone.
18	AMBLYGONITE	Amblygonite	White, Yellow, grey, blue-grey, green	5.5-6	2.98 - 3.11	Translucent	Common	Germany	Hydroxyy phosphate of aluminum	Amblygonite is a fluorophosphate mineral. The mineral occurs in pegmatite deposits and is easily mistaken for albite and other feldspars. Amblygonite forms a series with montebrasite, the low fluorine endmember.
19	AMETHYST	Quartz	Light to dark purple, violet	7	2.65	Transparent to Translucent	Common	Azerbaijan, Bulgaria, Cambodia, Chile, Finland, India, Kazakhstan, Laos, Malawi	Silicon Dioxide	Amethyst is a violet variety of quartz often used in jewelry. The name comes from the Ancient Greek a- ("not") and methustos ("intoxicated"), a reference to the belief that the stone protected its owner from drunkenness.
20	AMETHYST W/ AGATE	Quartz	Light to dark purple, violet	7	2.65	Transparent to Translucent	Common	Azerbaijan, Bulgaria, Cambodia, Chile, Finland, India, Kazakhstan, Laos, Malawi	Silicon Dioxide	Amethyst is a violet variety of quartz often used in jewelry. The name comes from the Ancient Greek a- ("not") and methustos ("intoxicated"), a reference to the belief that the stone protected its owner from drunkenness.
21	AMETRINE	Quartz	Red, Yellow, Black, Green, Blue	6½ - 7	2.6 - 2.65	Transparent to Translucent	Uncommon	Bolivia, Brazil, Canada, India, South Africa, USA	Silicon Dioxide	Ametrine, also known as trystine or by its trade name as bolivianite, is a naturally occurring variety of quartz. It is a mixture of amethyst and citrine with zones of purple and yellow or orange. Green-yellow or golden-blue ametrine does not exist naturally.
22	AMMOLITE	Fossilized	Blue, violet, green, red, pink	4.5 - 5.5	2.8	Opaque	Uncommon	USA & Canada	Calcium Carbonate	Ammolite is an 'opal like', organic gemstone that is formed from fossilized, extinct mollusks called Ammonites. Ammonites were a squid-like marine animal and existed through out the Paleozoic Era until the end of the Crustaceous Era.
23	AMMONITE	Organic Fossilized	Grey, brown, white, red, green	6 - 6½	2.8	Opaque	Uncommon	USA & Canada	Calcium Carbonate	Ammonites are excellent index fossils, and it is often possible to link the rock layer in which a particular species or genus is found to specific geological time periods.
24	AMPHIBOLIC ROCK	Metamorphic Rock	Black, green, white	5.5-6	2.85	Opaque	Common	Austria, Sweden, USA, Germany, France	Mineral Grouping	Amphibolite is a grouping of rocks composed mainly of amphibole and plagioclase feldspars, with little or no quartz. It is typically dark-colored and heavy, with a weakly foliated or schistose (flaky) structure.
25	AMPHIBOLITE W/ GARNET									See Amphibolic Rock
26	ANALCIME	Zeolite	Colorless, white, pink, yellow, green	5 - 5½	2.22 -2.29	Translucent to Opaque	Very Common	Angola, Armenia, Australia, Argentina, Azerbaijan, Bolivia, Brazil, Belgium	Hydrated Sodium Aluminum Silicate	Analcime is a popular and interesting mineral. It is sometimes known as analcite, although analcime is preferred.
27	ANATASE	Oxide minerals	Black, red, brown, yellow, dark blue, grey	5½ - 6	3.82 - 3.97	Transparent to Translucent	Uncommon	Bolivia, Brazil, Cameroon, Canada, Spain, Sudan, Sweden	Titanium Oxide	More commonly known as octahedrite, a name which, indeed, is earlier than anatase, and given because of the common (acute) octahedral habit of the crystals. Other names, now obsolete, are oisanite and dauphinite.
28	ANDALUSITE	Andalusite	Yellow-green, brown, grey-green	7½	3.05 - 3.20	Translucent to Opaque	Very Common	Andorra, Armenia, Burma, Egypt, Hungary, India	Aluminum Silicate	Andalusite is an Aluminum nesosilicate mineral. The variety chiastolite commonly contains dark inclusions of carbon or clay which form a checker-board pattern when shown in cross-section. A clear variety first found in Andalusia, Spain.
29	ANDERSONITE	Carbonate	Bright yellow green, green	2½	2.79 - 2.87	Translucent to Opaque	Uncommon	Hillside mine, Bagdad, Yavapai County, Arizona, USA	Hydrated Sodium Calcium Uranyl Carbonate	Andersonite is a rare uranyl carbonate mineral, that was only described in the last half century. It has a luster that seems to glow and in fact it is very fluorescent. Andersonite specimens will usually glow a bright lemon yellow in ultraviolet light.
30	ANDORITE	Orthorhombic	Dark steel-gray, may tarnish yellow or iridescent	3 - 3.5	5.33 - 5.37	Opaque	Common	Bolivia, China, France, Russia, USA	Lead Silver Antimony	Andorite was first described in 1892 for an occurrence in the Baia Sprie mine, Baia Sprie, Maramures County, Romania, and named for Hungarian amateur mineralogist Andor von Semsey Andorite occurs in low-temperature polymetallic hydrothermal veins.
31	ANDRADITE	Garnet	Green, black, brown, yellow-brown	6½ - 7	3.7 - 4.1	Translucent to Opaque	Uncommon	Ecuador, Finland, France, Germany, Greece, Greenland, India, Serbia	Calcium Iron Silicate	Andradite is a species of the Garnet Group.
32	ANGLESITE	Baryte	Yellow, green	2.5-3.0	6.3	Transparent to translucent		Tsumeb, Southwest africa	Lead Sulfate	Anglesite is a lead sulfate mineral with the chemical formula PbSO4. It occurs as an oxidation product of primary lead sulfide ore, galena.
33	ANGELITE		Colorless, white, yellow, gray, blue, orange-red, red, pink, purple	3 - 3.5	2.98	Transparent to translucent			Calcium sulfate	barite is useful as a weighting agent for drilling fluids in oil and gas exploration. Other uses are in added-value applications which include the car, electronics, TV screen, rubber, and glass ceramics and paint industry, radiation shielding and medical
34	ANNABERGITE	Vivianite	Green, rose, light grey-light green, white	1½ - 2½	3.07	Translucent to Opaque	Uncommon	Netherlands, New Zealand, Oman, Poland, Portugal, Romania, Turkey, Zimbabwe	Hydrated Nickel Arsenate	Annabergite is a mineral consisting of a hydrous nickel arsenate. Crystals are minute and capillary and rarely met with, the mineral occurring usually as soft earthy masses and encrustations.
35	ANORTHOCLASE	Feldspar	White,yellow, pink	6-6.5	2.57-2.6	Transparent		Sicily, Italy	sodium-aluminium silicate	Anorthoclase is doubly terminated anorthoclase crystal from Kinki Region, Honshu island, Japan
36	ANORTHOSITE	Feldspar	Colorless, red- grey, white	6 - 6½	2.74 - 2.76	Opaque	Common	Brazil, Cameroon, Canada, Chile, China, Cost Rica, Hungary	Calcium Aluminum Silicate	Anorthosite on Earth can be divided into two types: Proterozoic and Archean. These two types of anorthosite have different modes of occurrence, appear to be restricted to different periods in Earth's history, and are thought to have had different origins.
37	ANTHRACITE	Coal	Teal, black, blue-grey, green	3.0 - 3.8	1.3–1.4	Opaque	Uncommon	Austria, China, France, Germany, Switzerland, Ukraine, USA,	Complex Mixture	Anthracite are blue coal, hard coal, stone coal, blind coal (in Scotland), Kilkenny coal (in Ireland), crow coal (or craw coal from its shiny black appearance), and black diamond.
38	ANTIMONITE	Stibnite	Lead-grey with pale blue tint	2	4.63	Translucent to Opaque	Uncommon	Costa Rica, Cuba, Czech Republic, Ghana, Greece, Guatemala, Hungary	Antimony Sulfide	Stibnite has no significant uses, except as a precursor to antimony oxide, which is the most commonly marketed form of antimony. In ancient times, it was used as mascara called kohl.
39	APATITE	Apatite	colorless, pink, yellow, green, blue, violet	5	3.16 - 3.23	Translucent to Opaque	Very Common	Armenia, Brazil, Cameroon, Chile, Colombia, Cuba, Ecuador, Eritrea, Gabon	Calcium phosphate with chlorine, fluorite, Hydroxyyl	Apatite is one of few minerals that are produced and used by biological micro-environmental systems. Fluoro-Chloro Apatite forms the basis of the, now obsolete, Halophosphor fluorescent tube phosphor system. Is also called Cat's Eye.
40	APACHE GOLD STONE									Please check gold.
41	APOPHYLLITE	Apophyllite	Many Shades	4.5 - 5	2.3 - 2.4	Transparent to Translucent	Common	India, USA, Mexico, Iceland	Potassium Calcite Fluorite Hydroxide	The name apophyllite refers to a specific group of phyllosilicates, a class of minerals. Originally, the group name referred to a specific mineral, but was redefined in 1978 to stand for a class of minerals of similar chemical makeup that comprise a solid solution series.
42	AQUAMARINE	Beryl	Light blue to dark blue, blue-green	7½ - 8	2.68 - 2.74	Transparent to Translucent	Very Common	Malawi, Mongolia, Mozambique, Namibia, Nepal, Norway, Portugal, Vietnam, Zambia, Zimbabwe	Beryllium Aluminum Silicate	Aquamarine is a gemstone-quality transparent variety of beryl, having a delicate blue or turquoise color, suggestive of the tint of seawater. It is closely related to the gem emerald.
43	AQUAMARINE W/ MORGANITE									Please see Aquamarine and Morganite
44	AQUA NEVADA
45	AQUAPRASE									Please see Aquamarine
46	AQUA TEEN									Please see Aquamarine.
47	ARAGONITE	Aragonite	Colorless, white, brown, grey, yellow, red, pink, purple, orange, blue, green	3½ - 4	2.947	Translucent to Opaque	Common	Spain, Italy, Mexico, USA, Pakistan, Brazil	Calcium Carbonate	Aragonite is the second most common polymorph of natural calcium carbonate (the most common is calcite). It is significantly less widespread and abundant than calcite and is formed under a much narrower range of physio-chemical conditions.
48	ARSENOPYRITE	Arsenopyrite	Silver-white to steel-grey	5½ - 6	6.07	Opaque	Uncommon	Ghana, Uzbekistan, Vietnam, Zimbabwe	Iron Arsenic Sulfide	A major ore of arsenic, Arsenopyite can contain a small amount of gold as an impurity. Although an ore of arsenic, it is not intentionally mined for that reason.
49	ARTISANS									An artisan is a skilled manual worker who crafts items that may be functional or strictly decorative, including furniture, clothing, jewelry, household items, and tools. The term can also be used as an adjective to refer to the craft of hand making food products, such as bread, beverages and cheese.
50	ASBESTOS	Silicate	Lavender, blue, green, white	2 - 5	2 - 2.8	Translucent to Opaque	Common	Afghanistan, Angola, Australia, Austria, Belgium, Canada, China, Egypt, Finland, France, Germany	Sodium Iron Magnesium Silicate Hydroxyide	Asbestos is a naturally occurring silicate mineral with long, thin fibrous crystals. The word asbestos is derived from a Greek adjective meaning inextinguishable.
51	ASTEROID
52	ASTROPHYLLITE	Inosilicates	Golden brown to yellow, black, green	3½ - 4	3.2–3.4	Opaque	Uncommon	Mont-Saint-Hilaire, Quebec, Canada; Pikes Peak, Colorado, USA	Potassium Sodium Iron Manganese Titanium Silicate Hydroxyide	Astrophyllite is a very rare, brown to golden-yellow hydrous potassium iron titanium silicate mineral. Belonging to the astrophyllite group, astrophyllite may be classed either as an inosilicate, phyllosilicate, or an intermediate between the two.
53	ASTROPHYLLITE W/ EUDIALYTE									Please see Astrophyllite and Eudialite
54	AURICHALCITE	Carbonate	Pale green, sky blue, blue-green	1½	3.96	Transparent	Uncommon	Morocco, Namibia, Norway, Vietnam, Zambia	Zinc Copper Carbonate Hydroxyide	Aurichalcite is a carbonate mineral, usually found as a secondary mineral in copper and zinc deposits.
55	AUTUNITE	Autunite	Green-yellow, pale green, dark green	2 - 2½	3.05 - 3.2	Translucent to Opaque	Uncommon	Germany, Hungary, Italy, New Zealand, Slovakia, Uzbekistan	Hydrated Copper Uranium Phosphate	Autunite is one of the more attractive and popular radioactive minerals. The uranium in its chemical formula provides this radioactivity. Autunite is probably the most popular uranium mineral for collectors.
56	AVENTURINE	Beryl	Green, red-brown, gold-brown	7	2.64 - 2.69	Translucent to Opaque	Common	Austria, Germany, India, Slovakia, South Africa, USA,	Silicon Dioxide	Aventurine is generally cut into curved pieces for necklaces or other jewels, or for use as pendants, but is also much used for carving and figurines. Aventurine is a form of Quartz.
57	AZURITE	Azurite	Dark blue, violet	3½ - 4	3.7 - 3.9	Opaque	Common	Bulgaria, Canada, Chile, Hungary, Greenland, Jamaica, Japan	Hydroxyy of Copper Carbonate	Azurite is a soft, deep blue copper mineral produced by weathering of copper ore deposits. The blue of azurite is exceptionally deep and clear.
58	AZURMALACHITE	Carbonate	Blue and green, turquoise bands	3.5 - 4	3.70 - 3.95	Translucent to Opaque	Rare	United States, France, Nambia	Copper Carbonate Hydroxide	Azurite is a mixture of azurite and malachite. It is an attractive stone which combines vivid blue colour of azurite and saturated green colour of malachite. It can be cut into cabochons or used for small objects d'art.
59	BABINGTONITE	Calcium Iron Silicate	Green to Black and Brown	6	3.3	Translucent	Uncommon	India, China	Calcium Iron Silicate Hydroxide	Babingtonite is a calcium iron manganese inosilicate mineral. It is a very dark green to black translucent (in thin crystals or splinters) mineral crystallizing in the triclinic system with typically radial short prismatic clusters and druzy coatings.
60	BANDED HORNSTONE	Metamorphic Rock	Grey, light brown, black	7.5-8	3.05	Opaque	Uncommon	America, South America, Asia, Australia, Europe	Complex Silicate of Aluminium and Alkalies with Hydroxyl	Hornstones are fine-grained nonfoliated metamorphic rocks with no specific composition. They are produced by contact metamorphism. They are "baked" while near a heat source such as a magma chamber, sill or dike.
61	BANDED JASPER	Chalcedony Banded	All colors, mostly striped, or spotted	6½ - 7	2.58 - 2.91	Opaque	Common	Egypt, Australia, Brazil, India, Canada, Kazakhstan, Madagascar, Russia	Silicon Dioxide	Uniformly colored jasper is rare usually it is multicolored, striped or flamed. Sometimes jasper can be grown together with agate or opal.
62	BARITE	Barite	Colorless, brown, yellow, red, green, blue	3 - 3½	4.43 - 4.46	Transparent	Common	Spain, Germany, Canada, France, India, Romania and localities in US	Barium Sulphate	Barite is useful as a weighting agent for drilling fluids in oil and gas exploration. Other uses are in added-value applications which include the car, electronics, TV screen, rubber, and glass ceramics and paint industry, radiation shielding and medical applications.
63	BASALT	Pyroxene	Dark grey, dark green, dark brown, black	2	2.9	Opaque	Very Common	Czech Republic	Plagioclase feldspar, pyroxene, olivine, magnetite, and ilmenite	Basalt is a local material used for road paving and crushed stone for read and railroad ballast; also used in a minor way as building stone and as raw material for the production of rock wool and glass wool.
64	BASTNAESITE	Bastnasite	Pale white, tan, gray, brown, yellow and pink	4 - 4.5	4.7 - 5	Translucent to Opaque	Common	Sweden, Norway, Mongolia, Turkey	Cerium Lanthanum Yttrium Carbonate Fluoride	Bastnasite, which is sometimes spelled as bastnaesite, is one of a few rare earth carbonate minerals. It gets its name from its type locality, Bastnas Mine, Riddarhyttan, Vastmanland, Sweden., it is wide spread and one of the more common rare earth carbonates.
65	BATTEN JADE									See Jade
66	BAUXITE	Aluminum oxide	Beige, yellow, white, grey, brown	1½ - 2	2.8 to 3.25	Opaque	Very Common	Australia, Austria, Bosnia and Herzegovina, Brazil	Iron and Aluminum Hydroxyides	Bauxite is a naturally occurring, heterogeneous material composed primarily of one or more aluminum Hydroxyide minerals, plus various mixtures of silica, iron oxide, titania, aluminosilicate, and other impurities in minor or trace amounts.
67	BENAVIDESITE	Sulfosalt mineral	Lead Grey	2.7	5.6	Opaque	Uncommon	Japan, Peru, Romania, Sweden	Sulfosalt Sulfide	Benavidesite is a mineral group of sulfosalts.
68	BENITOITE	Metamorphic Rock	Light blue to deep indigo blue	6 - 6.5	3.6	Transparent to Translucent	Rare	USA, Japan	Barium titanium silicate	Benitoite was first discovered in 1907, and upon its initial discovery was thought to be Sapphire. The crystal structure of Benitoite is unique, and is the only significant mineral in its crystal class. It crystallizes in a rare hexagonal sub-class called ditrigonal-dipyramidal.
69	BERYL	Beryl	Gold-yellow, yellow-green, yellow, pink, colorless	7½ - 8	2.66 - 2.87	Translucent to Opaque	Common	Germany, Hungary, Italy, New Zealand, Slovakia, India, Uzbekistan, Italy	Beryllium Aluminum Silicate	Beryl is colorless in pure form; it is the many different impurities that give beryl its varied coloration. Beryl is praised for its transparency, high hardness, and beautiful colors with wide range of tones and shades.
70	BERYLLONITE	Beryl	White to Plate Yellow	5.5 - 6	2.8	Transparent to Translucent	Uncommon	USA, Brazil, Afghanistan	Sodium Beryllium Phosphate	Beryllonite is a rare beryllium mineral. It is found at only a few places around the world. It can be cut as gems, but lacks the color, fire, and hardness necessary to be a popular gemstone.
71	BIRDS EYE									Please check Rhyolite.
72	BIOTITE	Mica	Dark brown, green brown, dark brown, yellow, white	2.5-3	2.8 - 3.4	Opaque	Uncommon	Italy, Switzerland, Australia	Potassium iron magnesium aluminum silicate Hydroxyide fluoride	Biotite is a common phyllosilicate mineral within the mica group. It refers to the dark mica series, primarily a solid-solution series.
73	BISMUTHINITE	Aikinite	Lead grey to tin white	2 - 2½	6.78	Opaque	Uncommon	Bulgaria, Burundi, Canada, Chile, China, Hungary, India	Bismuth Sulfide	Bismuthinite is an important ore of bismuth. Sprays of steel gray prismatic bismuthinite crystals radiate outward from a common attachment point in the more spectacular specimens of this somewhat rare sulfide mineral.
74	BIXBITE	Beryl	Light red to dark red	7.5 - 8	2.67 - 2.84	Translucent to Opaque	Uncommon	USA	Beryllium Aluminum Silicate	Bixbite (or red beryl) is the red color variety of the beryl family of minerals. This gemstone gets its rich red coloring form the traces of manganese added to the basic beryl mineral formula. Bixbite is generally quite rare and is usually very small in size due it's scarcity.
75	BLADE CALCITE	Calcite	Colorless, blue, pink, orange, green, red, yellow, black, white	3	2.69 - 2.71	Translucent to Opaque	Uncommon	South Africa, Australia, Burma, India, Namibia, United States, Zambia, Germany	Calcium Carbonate	Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate. The other polymorphs are the minerals aragonite and vaterite.
76	BLUE LACE AGATE									Please see Agate
77	BLUE QUARTZ									Please see Quartz
78	BLUE SLAG COPPER									Please see copper.
79	BLUE TOPAZ	Topaz	Colorless, yellow, red-brown, light blue, pink-red, violet, light green	8	3.49 - 3.57	Translucent to Opaque	Uncommon	Brazil, Afghanistan, Burma, China, Japan, Madagascar, Mexico, Namibia, Nigeria,	Hydroxyy silicate of Aluminum with fluorite and iron	The name topaz is most probably derived from a place of discovery on an island in the Red Sea, now Zebirget but formerly Topazos. Colors of gemstone that is today called topaz are rarely vivid.
80	BOJI STONE
81	BOLEITE	Halides	Indigo blue, Light blue.	3-3.5	4.8-5.1	Transparent to subtranslucent		Boleo, Baja California, Mexico.	Hydroxychloride of potassium, lead, silver and copper	Boleite is a highly attractive, though uncommon, blue mineral that forms in very distinct crystal habits. Its crystals can be perfectly cubic, both in individual isolated crystals, and may be perched on fragile matrix
82	BOLTWOODITE	Uranium silicate mineral	Pale yellow	3½ - 4	4.7	Transparent to Translucent	Uncommon	Argentina, Australia, Czech Republic, France, Germany, Japan, Mexico	Hydrated Potassium Uranyl Silicate Hydroxyide	Boltwoodite is a hydrated potassium uranyl silicate mineral. It is formed from the oxidation and alteration of primary uranium ores.
83	BORACITE	Tektoborates	Whitish Green	7 - 7.5	2.91 - 3.1	Transparent to Translucent	Uncommon	England, India	Magnesium Borate Chloride	Boracite produces crystals of various colours with vitreous to adamantine lustre. It has good clarity and hardness, but it is slightly soluble in water. This fact limits the use of boracite as a gemstone. It is named so due to its high amount of Boron.
84	BORAX	Tincalconite-Borax	Colorless, grey, white, yellow, blue, green	2 - 2½	1.715	Translucent to Opaque	Uncommon	Argentina, Bolivia, China, India, Italy, Mexico, Turkey, USA	Hydrated Sodium Borate	The term borax is used for a number of closely related minerals or chemical compounds that differ in their crystal water content, but usually refers to the decahydrate.
85	BORNITE	Sulfide mineral	Brown, copper red	3	5.06 - 5.09	Opaque	Uncommon	Afghanistan, Argentina, Atlantic Ocean, Australia, Austria, Azerbaijan, Belgium, Bolivia, Brazil, Bulgaria, Canada	Sulfide of Copper and Iron	Bornite has a brown to copper-red color on fresh surfaces that tarnishes to various iridescent shades of blue to purple in places. Its striking iridescence gives it the nickname peacock copper or peacock ore.
86	BOTRYOIDAL CHALCEDONY									Please see Chalcedony
87	BOURNONITE	Bournonite	Steel-grey, black	2½ - 3	5.83	Opaque	Uncommon	Argentina, Australia, Austria, Bolivia, Bulgaria, Canada, Channel Islands, Chile, China, Colombia, Ethiopia, Fiji	Lead Copper Antimony Sulfide	Bournonite is a sulfosalt mineral species, a sulfantimonite of lead and copper.
88	BOUSSINGAULTITE	Picromerite	Colorless, Yellow pink, Light yellow, Pink.	2	1.7	Transparent	Uncommon	Tuscany, Italy	Sulfate mineral	Boussingaultite is monoclinic symmetry and forms clear, often rounded crystals.
89	BRAZILIANITE	Phosphate	Yellow, green, colorless	4.5 - 5	2.45	Transparent to Translucent	Uncommon	Brazil, USA	Sodium Aluminum Phosphate Hydroxide	Brazilianite, whose name derives from its country of origin, Brazil, is a typically yellow-green phosphate mineral, most commonly found in phosphate-rich pegmatites. One noted deposit of brazilianite is in the surroundings of Conselheiro Pena, in Minas Gerais, Brazil.
90	BRECCIATED WHITE									Please check jaspher.
91	BROOKITE	Oxide minerals	Brown, yellow- brown, red-brown	5½ - 6	4.08 - 4.18	Transparent to Translucent	Uncommon	Australia, Belarus, Belgium, Brazil, Bulgaria, Canada, Chile, France, Germany, Greece, Hungary, Italy, Madagascar, Morocco	Titanium Oxide	Brookite is orthorhombic, and one of the four naturally occurring polymorphs (minerals with the same composition but different structure). Brookite is rare compared to anatase and rutile and, like these forms, it exhibits photocatalytic activity.
92	BRONZITE	Pyroxene	Greenish brown	5.5	3.35	Transparent,To opaque			magnesium iron silicate	Bronzite is an iron-bearing variety of Enstatite from Austria. It has green-brown colour with bronze-like sub-metallic lustre. It was known long before Enstatite.
93	BRUCITE	Brucite	White, pale green, blue, gray	2.5-3	2.39 - 2.4	Transparent		New Jersey, USA	Magnesium hydroxide	Brucite is most often in crude, uninteresting form, but several localities produce distinct and interesting crystals which are highly desirable to collectors. Brucite may form as a standalone mineral.
94	BRUNO JASPER									Please check jasper.
95	BUDDSTONE	Chalcedony	Leek-Green, Yellow-Green	7	2.61	Translucent to Opaque	Uncommon	Australia, Brazil, India, Kazakhstan, Madagascar, Russia, Zimbabwe, South Africa, Tanzania	Silicon dioxide	The name buddstone has been given to a green chlorite-rich Chrysoprase with white veining, found in southern Africa.
96	BUMBLE BEE JASPER								Calcium carbonate
97	BUTTE
98	BUTTER JADE									Please see Jade
99	BYRATO CALCITE	Monoclinic	Colourless, white, greyish, greenish, light yellow	4	3.66 - 3.71	Transparent, Translucent	Common	England, UK		Byrato calcite has at least one perfect and one imperfect cleavage. It is a brittle mineral, and breaks with an uneven to conchoidal fracture.
100	BYSTRITE	Cancrinite	Yellow	5	2.43	Transparent to Translucent	Uncommon	south of Lake Baikal, Siberia, Russia	Silicate mineral	Bystrite has a structure that is shared with many of the minerals in the cancrinite group. It exhibits a hexagonal crystal structure with a 3m point group. The structure of bystrite could not be easily found due to the mineral exhibiting a strong pseudotranslation.
101	BYTONITE	Feldspar	Colorless, grey, white	6 - 6.5	2.72 - 2.74	Transparent to Translucent	Uncommon	South Africa, Mexico, Canada, UK, USA	Calcium Sodium Aluminum Silicate	Bytownite is a rarer form of feldspar, more commonly seen as a faceted gemstone then as a collectors mineral. It is usually translucent without a crystal form.
102	CACOXENITE		Yellow to brownish yellow, reddish orange, golden yellow, deep orange, green	3-4	2.2-2.6	Translucent	Common	Bohemia, Czech	Iron aluminium phosphate	Cacoxenite is just something that forms inside of an Amethyst or other gemstone, displaying as rutile or golden tufts. However, there are the rare occasions when this becomes its own visually appealing gemstone.
103	CALCITE	Calcite	Colorless, blue, pink, orange, green, red, yellow, black, white	3	2.69 - 2.71	Translucent to Opaque	Uncommon	South Africa, Australia, Burma, India, Namibia, United States, Zambia, Germany	Calcium Carbonate	Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate. The other polymorphs are the minerals aragonite and vaterite.
104	CALCITE W/ PYRITE									See Calcite and Pyrite
105	CAMPYLITE		White	3.5 - 4						Campylite is a variety of the lead arsenate mineral mimetite which received the name from the Greek 'kampylos'- bent, on account of the barrel-shaped bend of its crystals. It has also been used as an alternate name for pyromorphite.
106	CARNELIAN	Chalcedony	Pale orange, red	6½ - 7	2.58-2.64	Translucent to Opaque	Uncommon	France, Germany	Silicon Dioxide	Carnelian (also spelled cornelian) is a reddish-brown mineral which is commonly used as a semi-precious gemstone. Similar to carnelian is sard, which is generally harder and darker.
107	CARNOTITE	Carnotite	Yellow, golden yellow, green-yellow	2	4.7	Opaque	Uncommon	Kazakhstan, Madagascar, Mexico, Morocco, Namibia, Norway, Spain	Hydrated Potassium Uranium Vanadate	Carnotite is a relatively uncommon mineral, yet common enough to be an important ore of uranium and vanadium.
108	CARROLITE	Linnaeite	Bright silver color	4.5-5.5	4.5-4.8	Opaque		Maryland,USA	Sulfide of copper and cobalt	Carrollite from Kambove, Katanga. This specimen is 4.3 cm wide, with a 1.2 cm carrollite crystal partly covered by pyrite, between calcite crystals.
109	CASSITERITE	Cassiterite	Black, yellow, brown, red, white	6 - 7	6.98 - 7.01	Translucent to Opaque	Uncommon	Bulgaria, Burma, Burundi, Ecuador, Finland, Greece, Greenland, Indonesia, Ireland, Norway	Tin Oxide	Cassiterite's name is derived from the term “Cassiterides” which was applied 'islands off the western coast of Europe' in pre-Roman times.
110	CATAPLEIITE	Zirconium	Blue, gray, yellowish-brown, reddish or colorless	5 - 6	2.8	Transparent to Translucent	Uncommon	USA, Madagascar, Norway, Canada	Hydrated Sodium Zirconium Silicate	Catapleiite is a rather rare zirconium mineral. It forms in alkaline rocks and rare rocks known as agpaites which are igneous rocks of unusual concentrations. They are characterized by high concentrations of alkali metals.
111	CAT'S EYE									See Chrysoberyl
112	CAVANSITE	Zeolite	Green Blue to Ink Blue	3 - 4	2.25-2.33	Transparent to Translucent	Uncommon	India, USA	Calcium Vanadium Silicate Hydroxide	Cavansite is a beautiful and rare mineral. It was only discovered in the last 30 years and is found in only a few locallities. By far the best crystals come from the famous zeolite quarries in Poona, India. Crystal aggregates consist of spherical rosettes with jutting pointed crystals. The deep blue color of even the smallest cavansite crystals is truly amazing.
113	CELESTITE	Baryte Group	Colorless, milky white, pale blue, yellow	3 - 3.5	3.96	Transparent to Translucent	Common	England, Italy, USA	Strontium Sulfate	Celestite is used in nuclear industry in the manufacture of rubber, paint and electrical batteries in the refining of beet sugar and in the preparation of iridescent glass and porcelain.
114	CERUSSITE	Carbonate	Colorless, white, cream, light gray, light yellow, and brown	3 - 3.5	6.5 - 6.6	Transparent to translucent	Common	USA, Nambia, Morocco, England, New Mexica	Lead Carbonate	Cerussite is an interesting mineral, forming in an array of fascinating crystal formations and bizarre twinning habits. It is easily identifiable by its heavy weight, brilliant luster, and crystal habits. Cerussite also performs interesting reactions during blowpipe testing. Specimens may be fragile and should be handled with care.
115	CHABAZITE	Zeolite	Colorless, Red, Yellow, Pink, Green	3 - 5	2 - 2.2	Transparent to Translucent	Common	India, Iceland, USA, Nova Scotia, Germany, Switzerland	Calcium Sodium Potassium Aluminium Silicate Hydroxide	Chabazite, also known as acadialite, is one of the lesser known zeolites, but still a popular one to collect. Chabazite forms in the petrified bubbles of volcanic rocks that have had a slight amount metamorphism.
116	CHALCANTHITE	Sulfate	Bright blue, sky-blue, greenish-blue	2.5	2.17 - 2.28	Transparent, Translucent	Rare	Spain, Chile, England	Hydrated Copper Sulfat	Chalcanthite is natural, water-soluble copper sulphate. A secondary mineral that is formed in arid climates or in rapidly oxidizing copper deposits. It is usually of post-mining formation, forming on mine walls and by the action of acidic surface waters on copper veins.
117	CHALCEDONY	Chalcedony	White, grey, green, yellow, brown	6½ - 7	2.58 - 2.64	Translucent to Opaque	Very Common	Belize, Denmark, Eritrea, Eritrea, Greenland, India	Silicon Oxide	Traditionally defined as a fibrous cryptocrystalline variety of Quartz, more recently, it has been shown that much Chalcedony is a mixture of Quartz and Morganite (silica mineral). When it is concentrically banded it is called by the sub variety name Agate.
118	CHALCOPYRITE	Chalcopyrite	Brass yellow, bright golden	3.5 - 4	4.1 - 4.3	Opaque	Very Common	Zambia, USA, Zaire, Chile, Norway, Spain	Copper Iron Sulfide	One of the most important copper ores. Yielding the by-products gold and silver. About 80 percent of the world's copper is derived from the treatment of chalcopyrite ore. The minerals referred to as "Fool's Gold" because of its bright golden color.
119	CHALCOCITE	Sulfide	Blue black, gray, black, black gray, or steel gray	2.5 - 3	5.5 - 5.8	Opaque	Uncommon	England, St. Ives, Nambia, Kazakhstan	Copper Sulfide	Chalcocite is a coveted and iconic mineral among collectors. Specimens from classic and extinct localities, such as Cornwall, England and Bristol, Connecticut, will command extremely high prices, especially when in good crystals.
120	CHAROITE	Silicates	Lilac to violet, in various shades	2.54 - 2.78	1.55 - 1.59	Translucent to opaque	Rare	Russia	Phosphorus, Calcium, and Sodium	Charoite is a rare silicate mineral with a very complex chemical composition of phosphorus, calcium, and sodium. It's considered to be a relatively new gemstone,
121	CHIASTOLITE	Silicate	Reddish brown, olive green, white to gray	6.5 - 7	3.17	Translucent to Opaque	Uncommon	United States, South Africa, Australia, France	Aluminum silicate	A variety of Andalusite Crystals of Andalusite containg cross-shaped inclusions of carbon. Common in some metamorphic rocks.
122	CHLORITE	Chlorite	Colorless, light to dark green, gray-green, black	2 - 2½	2.6 - 3.3	Translucent to Opaque	Common	India, Cuba, Japan, Morocco, Namibia, Mongolia, Mexico, New Zealand, Niger, Nigeria	Chlorate	The chlorites are a group of phyllosilicate minerals. Chlorites can be described by the following four endmembers based on their chemistry via substitution of the following four elements in the silicate lattice; Mg, Fe, Ni, and Mn.
123	CHROME DIOPSIDE	Diopside	Colorless, Yellowish To Yellow, Brown, Black, Blue, Green Or Red, Pink, Champagne-Tan, Cognac-Brown, Lilac	6½	3.22 - 3.38	Transparent to Translucent	Common	China, Myanmar, India, Madagascar, South Africa, Tanzania, Russia, Finland, Italy, Austria	Calcium magnesium silicate	Diopside variety with strong emerald-green color
124	CHROMITE	Spinel	Black, brown, dark grey	5½	4.5 - 4.8	Opaque	Common	Albania, Cyprus, Ethiopia, Gabon, Germany, Ghana, Libya, New Caledonia, Oman, Russia	Iron Chromium Oxide	Chromite is also used as a refractory material, because it has a high heat stability.The only ore of chromium is the mineral chromite.
125	CHROMIUM	Metal	White, grey, silver	9	7.19	Opaque	Common	Australia, China, Japan, Russia	Chromium	Chromium was regarded with great interest because of its high corrosion resistance and hardness. A major development was the discovery that steel could be made highly resistant to corrosion and discoloration by adding chromium and nickel to form stainless steel.
126	CHRYSANTHEMUM	Aragonite								It is an ornamental stone displaying chrysanthemum-like patterns in a contrasting matrix. Marketed specimens are often highlighted by selective painting of the matrix with a dye to over-emphasise the crystal pattern, which in the process obliterates some of it.
127	CHRYSOBERYL	Chrysoberyl	Golden-yellow, green-yellow, green, brown, red	8½	3.70 - 3.78	Transparent to Translucent	Uncommon	Brazil, Sri Lanka, Myanmar, Madagascar, Zimbabwe, Russia	Beryllium Aluminate	Chrysoberyl has been known since antiquity; the varieties alexandrite and chrysoberly cat's eye are especially valued.
128	CHRYSOCOLLA	Chrysocolla	Green, blue	2 - 4	2.00 - 2.40	Opaque	Common	Chile, Israel, Mexico, Peru, Russia, the United States (Nevada) and Zaire	Hydrated Copper Silicate	Chrysocolla is a sharply colored mineral. Its color can be among the brightest shades of blue and green, and is caused by its copper content. Chrysocolla is often coated by a drusy layer of glossy clear Quartz or intergrown together with the Quartz.
129	CHRYSOCOLLA W/ MALACHITE									Please see Chrysocolla and Malachite
130	CHRYSOPRASE	Chalcedony	Green, apple-green	6½ - 7	2.58 - 2.64	Translucent to Opaque	Uncommon	Australia, Brazil, India, Kazakhstan, Madagascar, Russia, Zimbabwe, South Africa, Tanzania	Silicon Dioxide	Chrysoprase is considered the most valuable stone in the chalcedony group. The coloring agent is nickel.
131	CHRYSOTILE	Serpentine	Light green, dark green	2½-3	2.53	Translucent to Opaque	Very Common	Cuba, Ethiopia, Germany, Greenland, Morocco, New Zealand, Poland, Slovakia	Hydrous magnesium silicate	An industrial mineral widely used for thermal or electrical insulation.
132	CINNABAR	Sulfide mineral	Red, pink	2 - 2½	8.176	Opaque	Uncommon	Chile, Georgia, Germany, Hungary, Kyrgyzstan, Mongolia, Peru, Slovakia	Mercury sulfide	Most important ore of mercury, as the native element is very rare. It was used in the past as the mineral pigment known as vermillion.
133	CIRNOID FOSSIL									Please check fossil.
134	CITRINE	Quartz	Light yellow, orange	7	2.65	Transparent	Uncommon	Brazil, Madagascar, United States, Argentina, Myanmar, Namibia	Silicon Dioxide	The name is derived from its lemon-yellow color. Most commercial citrines are heated-treated amethysts. Almost all heat-treated citrines have a red tint. The natural citrines are mostly pale yellow.
135	CLAMSHELL FOSSIL	Mollusca
136	CLINOCHLORE	Chlorite	Green, Red, Brown, Yellow	2 - 2.5	2.6 - 3	Transparent to Translucent	Common	USA, Austria, Italy, Spain, Scotland, Switzerland	Magnesium Iron Aluminum Silicate Hydroxide	Clinochlore is one of the more common members of the Chlorite Group of minerals. These minerals are all difficult to differentiate by ordinary means and often the general mineral name chlorite is given to specimens that lack distinguishing characterics.
137	COAL	Carbon	Black	3	1.1-1.4	Opaque	Very Common	Peru, Sweden, Spain, Turkey, Switzerland, Switzerland, Ukraine, USA	Mainly Carbon (Mixed)	A sedimentary rock of organic origin consisting predominantly of carbonised plant remains.
138	COBALT	Metal	Metallic grey	5.0	8.9	Translucent to Opaque	Uncommon	Russia	Cobalt	Cobalt is a bluish-gray, shiny, brittle metallic element. Its atomic number is 27 and its symbol is Co. It has magnetic properties like iron.
139	COBALT W/ CALCITE									Please see Cobaltocalcite
140	COBALTITE	Sulfosalt mineral	Red-silver white, violet steel grey, or black	5½	6.33	Translucent to Opaque	Uncommon	Botswana, Bulgaria, Hungary, North Korea, Poland, Saudi Arabia, Zimbabwe	Cobalt arsenic sulfide	Cobaltite although rare is still an important and valuable ore of cobalt, a strategically and industrially useful metal.
141	COBALTOCALCITE	Calcite	Colorless, white, grey, yellow, green	3	2.71	Translucent	Uncommon	Spain	Cobalt Carbonate	Cobaltocalcite refers to an intermediary mineral between Calcite and Sphaerocobaltite in a solid solution series. It is generally looked at as a cobalt-rich variety of Calcite, but can also be looked as a calcium-rich variety of Sphaerocobaltite.
142	COLE (See Colemanite)									Please see Colemanite
143	COLEMANITE	Inoborates	Colorless, white, yellow, grey, colorless	4½	2.423	Transparent to Translucent	Uncommon	Serbia, Turkey, USA, Greece, Kazakhstan	Hydrated calcium borate	Colemanite forms small but richly faceted crystals. The short prismatic habit is typical and good crystals with complicated faces are sought after by collectors.
144	COLORED GEMSTONES									Colored gemstones are pieces of minerals, which, in cut and polished form, are used to make/decorate jewelry or other adornments.
145	COLUMBITE	Oxide minerals	Black, brown-black	6	5.04	Opaque	Uncommon	Equatorial Guinea, Finland, Ghana, Mozambique, Niger, Norway, Poland, Portugal, Uganda	Iron manganese niobium tantalum oxides	Columbite, also called niobite, is a black mineral group that is an ore of niobium. It has a submetallic luster and a high density and is a niobate of iron and manganese.
146	CONDOR AGATE									Please see Agate
147	CONGLOMERATE STONE	Sedimentary	Light brown, grey yellow	2.5	1.7 - 2.3	Opaque	Common	Various Places	Heterogeneous Mixture	A conglomerate is a rock consisting of individual clasts within a finer-grained matrix that have become cemented together. Conglomerates are sedimentary rocks consisting of rounded fragments.
148	CONGLOMERATE JASPER	Chalcedony	Red, yellow, brown, green, blue	6½ - 7	2.58 - 2.91	Opaque	Common	Egypt, Australia, Brazil, India, Canada, Kazakhstan, Madagascar, Russia	Silicon Dioxide	The appeal of Jasper is its interesting color patterns and formations. Though it can be a solid color, it is most often mottled, spotted, ringed, or striped. Each Jasper has a unique color or pattern, lending this gemstone much variety. Jasper is an opaque form of Chalcedony.
149	COPAL	Organic Amber	Yellow, white, red, green, blue, brown, black	2 - 3	1.05 - 1.09	Transparent to Translucent	Common	Austria, Madagascar, New Zealand, UK	Carbon, Hydrogen and Oxygen	Copal is a solidified, volatile, rich plant resin, that can be colorless, yellow, brown or rarely reddish. It is a relatively recent fossil resin, which may have only tens or hundreds of years unlike Amber (millions years). Copal is frequently used as an imitation of Amber.
150	COPPER	Copper	Copper-red	2½ - 3	8.94 - 8.95	Opaque	Common	Costa Rica, Cuba, Denmark, Eritrea, Germany, Guatemala, Israel, Jamaica, Laos, Mongolia	Copper Sulfide	Pure copper is rather soft and malleable and a freshly-exposed surface has a pinkish or peachy color. Gold, caesium and copper are the only metallic elements with a natural color other than gray or white.
151	COPPER ORE									Please see Copper
152	COPPER W/ ROCK									Please see Copper
153	COPPER FIREBRICK	Copper	Copper-red	2½ - 3	8.94 - 8.95	Opaque	Common	Costa Rica, Cuba, Denmark, Eritrea, Germany, Guatemala, Israel, Jamaica, Laos, Mongolia	Copper Sulfide	Pure copper is rather soft and malleable and a freshly-exposed surface has a pinkish or peachy color. Gold, caesium and copper are the only metallic elements with a natural color other than gray or white.
154	COPROLITE
155	CORAL	Organic Amber Coral	Red, pink, white, black, blue	3 - 4	2.60 - 2.70	Opaque	Common	Western Mediterranean countries, the Red sea, bay of Biscay, Canary Island, Japan	Naturally Occuring	Most corals have built reef and atolls with their branching trunks. Unworked coral is dull when polished it has vitreous luster. It is polished with fine-grained sandstone and is used for beads for necklaces/bracelets.
156	CORDIERITE SUNSTONE	Silicate	Grey, blue, blue-violet, green, yellow brown, colorless	7 - 7½	2.6 - 2.66	Opaque	Uncommon	Myanmar, Brazil, India, Madagascar, Sri lank and United States	Magnesium Aluminum Slicate	The name is drived from its lemon-yellow color. Most commercial citrines are heate-treated amethysts. Almost all heat-treated citrines have a red tint. The natural citrines are mostly pale yellow.
157	CORINDON
158	CORN SHELL									See Shell
159	CORNELIAN AGATE									Please see Cornelian (Carnelian) and Agate
160	CORUNDUM	Corundum	Colorless, blue, red, pink, yellow, grey, golden-brown	9	3.98 - 4.1	Translucent to Opaque	Common	Bulgaria, Burma , Finland, India, Kyrgyzstan, Madagascar	Aluminum Oxide	Corundum is a crystalline form of Aluminum. It is one of the naturally clear transparent materials, but can have different colors when impurities are present.
161	COVELLITE	Sulfide mineral	Indigo blue, light blue, dark blue, black	1.5 - 2	4.6 - 4.8	Opaque	Uncommon	Mt Vesuvius, Somma-Vesuvius Complex, Naples Province, Campania, Italy	Copper Sulfide	Covellite is a rare copper sulfide mineral. This indigo blue mineral is ubiquitous in copper ores, it is found in limited abundance and is not an important ore of copper itself. It has a large amount of Graphite in it.
162	CREEDITE	Monoclinic	white, violet, colourless	4	2.71	Transparent		Colorado, USA	calcium aluminium sulfate fluoro hydroxide mineral	Creedite is a rare hydroxylhalide mineral. Creedite usually forms from the oxidation of fluorite ore deposits.
163	CROCIDOLITE
164	CRYSTAL	Quartz	Colorless to Pink, white, grey, yellow, brown, golden brown	7	2.65	Transparent to Translucent	Uncommon	Brazil, Madagascar, India, Mozambique, Namibia, Sri Lank and United States.	Silicon Dioxide	A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions.
165	CSARITE
166	CUPRITE	Cuprite	Brown red, purple red, red, black	3½ - 4	6.14	Translucent to Opaque	Common	Belgium, Bolivia, Bulgaria, Cuba, Hungary, Jordan, Luxembourg, Spain, Sweden	Oxide of Copper	Cuprite has been a major ore of copper and is still mined in many places around the world. Of all the copper ores except for native copper, cuprite gives the greatest yield of copper per molecule
167	CUPRITE W/ CHRYSOCOLLA									Please see Cuperite and Chrysocolla
168	CUPROSKLODOWSKITE	uranium	Grass green, Green yellow, Light green.	4	3.8	Transparent to Translucent		Katanga province, Belgian Congo		Cuprosklodowskite is a nesosilicate mineral, It is grass green to dark green in color, and its crystal habit is typically acicular, flat bladed crystals. It is a strongly radioactive mineral.
169	CYLINDRITE	Triclinic	Lead gray, Grayish black.	2.5	5.4 - 5.42	Opaque	Common	Poopo, in Oruro, Boliva	Sulfosalt minerals	Cylindrite Group from the Greek ?????d??s, a roll, in allusion to the typical cylindrical habit of the mineral.There is a relation between the cylindrical morphology and crystal structure. The latter is composite and characterizes in incommensurate modulations.
170	DANBURITE	Tectosilicates	Clear or white, shades of yellow and pink	7 - 7.5	3	Transparent to Translucent	Uncommon	USA, Mexico, Japan, Switzerland	Calcium boron silicate	Danburite is a commonly occurring mineral; large and facetable gemstone quality material is considered especially rare. Today, it is one of the lesser-known gemstones and is primarily classified as a collector's gem.
171	DATOLITE	Datolite	White, colorless, yellowish, reddish, gray, brown	5 - 5.5	2.8 - 3	Transparent to Translucent	Common	USA, Canada, Mexico, Germany, Norway	Calcium Boron Silicate Hydroxide	Datolite is a popular mineral among mineral collectors although it is somewhat obscure. It is often found in basalt vesicles with calcite and zeolites. In fact, it is often confused with certain zeolites because of its luster, color and associations.
172	DENDRITE									It is design, adjective and descriptive term.
173	DENDRITE OPAL									Please see Opal
174	DENDRITIC AGATE									Please see Agate
175	DENDRITIC PYROLUSITE									Please see Pyrolusite
176	DESMINE (Stilbite)	Zeolite	Colorless, white, pink	3½ - 4	2.18 - 2.2	Translucent to Opaque	Common	Bosnia & Herzegovina, Brazil, Bulgaria	Hydrated Sodium Calcium Aluminum Silicate	Desmine is synonym of Stilbite.
177	DIAMOND	Diamond	Colorless, yellow, brown, black, blue, green, red, pink, champagne-tan, lilac	10	3.5 - 3.53	Transparent	Uncommon	worldwide, especially in Angola, Australia, South Africa, Namibia, Brazil, Congo, Russia, Sierra Leone, Zimbabwe	Carbon	The name diamond refers to hardness. It has been recognised with various types of diamond with different characteristics. Due to the optical effects, the high hardness and its rarity, the diamondis considered the king of gemstones.
178	DIASPORE	Diaspore	White, green-grey, grey-brown, yellow, colorless	6.5 - 7	3.3 - 3.5	Translucent to Opaque	Common	Russia, Worldwide	Hydroxyy Aluminum Oxide	Diaspore is one of the three component minerals of the economically important aluminum ore Bauxite.
179	DICKITE	Phyllosilicates	Blue, Colorless, Gray, Yellow brown, White	1.5 - 2	2.6	Translucent to Opaque	Common	United States, Jamaica, Mexico	Phyllosilicates Clay	Dickite is chemically composed of 20.90% aluminium, 21.76% silicon, 1.56% hydrogen and 55.78% oxygen. It has the same composition as kaolinite, nacrite, and halloysite, but with a different crystal structure (polymorph). Dickite sometimes contains impurities such as titanium, iron, magnesium, calcium, sodium and potassium.
180	DIESEL									Diesel or diesel fuel in general is any fuel used in diesel engines. The most common is a specific fractional distillate of petroleum fuel oil, but alternatives that are not derived from petroleum.
181	DINOSAUR EGG									It’s a fossilized conversion of a Dinosaur Egg. Once it is hardened, it becomes a stone or mineral. Can be carved.
182	DIOPSIDE	Diopside	Light to dark green, blue, brown, snow white, grey, colorless	5½ - 6½	3.22 - 3.38	Translucent to Opaque	Very Common	Myanmar, Finland, India, Madagascar, Austria, Sri Lanka, South Africa	Calcium Magnesium Silicate	Named (Greek-double appearance) because of its crystal shape. Diopside is an important rock forming mineral in several metamorphic and basic to ultra-basic igneous rocks, also found in meteorites.
183	DIOPTASE	Dioptase	Emerald green, blue-green	5	3.28 - 3.35	Transparent to Translucent	Uncommon	Chile, Kyrgyzstan, Namibia, Peru, Russia, United States, Zaire	Hydroxyy Silicate of Copper	Dioptase is popular with mineral collectors and it is occasionally cut into small emerald-like gems. Dioptase and chrysocolla are the only relatively common copper silicate minerals.
184	DIORITE	Plutonic	Black and white	2.8 - 3	2.72 - 2.99	Opaque	Common	Italy, Germany, Finaland, Romania, New Zealand, USA, Egypt	Silicon Dioxide	A group of plutonic rocks intermediate in composition between acidic and basic, characteristically composed of dark-colored amphibole, pyroxene, and sometimes a small amount of quartz; also, any rock in that group; the approximate intrusive equivalent of andesite.
185	DOLOMITE	Dolomite	Colorless, white, grey, red-white, brown-white, pink, colorless	3½ - 4	2.84 - 2.86	Translucent to Opaque	Very Common	Angola, Antarctica, Armenia, Bahamas, Greece, Mozambique	Calcium Magnesium Carbonate	Dolomite is used as an ornamental stone, a concrete aggregate, a source of magnesium oxide and in the Pigeon process for the production of magnesium.
186	DOMEYKITE	Arsenide mineral	Tin-white to steel-gray	3 - 3.5	7.2 - 8.1	Opaque	Common	USA, Canada	Copper Arsenide	Domeykite is a semi-metal alloy of copper and arsenic. It is found at several copper mines in Chile and is named for a nineteenth century Chilean mineralogist named Ignacio Domeyko. Alloys are usually placed in the Elements Class.
187	DRAGON STONE									Another name for Serpentine. See Serpentine.
188	DRAVITE	Tourmaline	Pale to dark brown, dark yellow	7	3.03 - 3.18	Translucent to Opaque	Common	Finland, India, Kenya, Nepal, North Korea, Norway, Slovenia, Spain, Tajikistan, Tanzania, Uzbekistan, Zambia	Crystal Boron Silicate	Dravite is a brown variety of tourmaline. It is an ideal stone for self-healing, aids in finding emotional strength and self-acceptance. Dravite inspires courage and persistence.
189	DRUZY SPECTROPYRITE									Please see pyrite.
190	DRUZY QUARTZ
191	DUMORTIERITE	Dumortierite	Blue, brown, violet, green blue, pink	7	3.3 - 3.4	Opaque	Common	USA, France	Borosilicate of Aluminum and iron oxide	Dumortierite is a fibrous variably colored aluminum boro-silicate mineral. It is used in the manufacture of high grade porcelain. It is sometimes mistaken for Sodalite and has been used as imitation lapis lazuli.
192	ECLOGITE	Plutonic	Red, pale green	5 to 6	3.29 - 3.39	Opaque	Common	Greenland, Scotland, Italy, USA, Australia	Plagioclase feldspar, pyroxene, olivine, magnetite, and ilmenite	Eclogite is a dense, green plutonic rock composed of coarse grains of green, sodium-rich pyroxene and pale pink, magnesium rich garnet; Kyanite and rutile are also common. Chemically, an eclogite is equivalent to basalt.
193	ECLOGITE W/ GLAUCOPHANE									Please see Ecolgite and Glaucophane
194	ELBAITE	Tourmaline	Green, red to pink, blue, orange, yellow, colorless, multicolored	7.5	2.9 - 3.2	Transparent to Opaque	Common	Afghanistan, Austria, Canada, Brazil, Czech Republic, Italy, Madagascar	Sodium Lithium Aluminum Boro-Silicate Hydroxyide	Elbaite is a desirable member of the tourmaline group because of the variety and depth of its colours and quality of the crystals.
195	ELDARITE	Fossil/Volcanic Rock	Dark Green to Black	6.5 - 7	2.56	Opaque	Common	China, Mexico, Africa	Silicon Dioxide	Eldarite is certainly an unusual and handsome lapidary material. It is not mined by blasting, so it has few cracks or stresses that can affect specimens as they are worked.
196	ELECTRICITY									Electricity is a broad term encompassing the family of phenomenon arising from interaction between charged particles. Of the four fundamental forces of nature, the electromagnetic force is the most influential in our everyday lives.
197	ELMWOOD FLUORITE									Please see Fluorite. Fluorite mined from Elmwood mines.
198	EMERALD	Beryl	Green shades, colorless	7 1/2 - 8	2.67 - 2.78	Transparent to Opaque	Uncommon	Afghanistan, Australia, Austria, Brazil, Bulgaria, Canada, China, Egypt, Ethiopia	Beryllium Aluminum Silicate	The name emerald derives from Greek 'smaragdos'. It means ' green stone'. The physical properties, especially the density, refractive index and refraction
199	ENARGITE	sulfides	Steel gray, Blackish gray, Violet black.	3	4.4 - 4.5	Opaque	Common	Butte, Montana, USA	copper arsenic sulfosalt	Enargite is a sulfosalt mineral that is an import ore of copper. Crystals are sometimes coated with a thin layer of Pyrite crystals, giving it a yellow appearance. Enargite is dimorphous with the mineral Luzonite, which forms in tetragonal crystals.
200	EPHESITE	Mica	Brownish pink, Pearl gray, Pale green	3.5-4.5	2.98	Opaque	Uncommon	Ephesus, Turkey	phyllosilicate	Ephesite found in its natural state is translucent and pink in color. It has a vitreous luster and pearly on the cleavages.
201	EPIDOTE	Epidote	Green, black-brown	6 - 7	3.3 - 3.5	Translucent to Opaque	Common	Brazil, Kenya, Mexico, Mozambique, Norway	Hydroxy Silicate of calcium, aluminum and iron	Epidote is a calcium aluminum iron sorosilicate mineral. Epidote is an abundant rock-forming mineral, but one of secondary origin. It occurs in marble and schistose rocks of metamorphic origin.
202	EPIDOTE IN CRYSTAL									Please see Epidote and Crystal
203	EPIDOTE W/ JASPER									Please see Epidote and Jasper
204	EPISTILBITE	Zeolite	White, Pink and Red	4 - 4.5	2.2 - 2.3	Transparent to Translucent	Uncommon	India, Iceland, Italy, Hawaii	Calcium Sodium Aluminium Silicate Hydroxide	Epistilbite is a rare member of the zeolite group. It has a very similar chemical makeup to Stilbite, and can be difficult to distinguish from Stilbite. Epistilbite is not dimorphous with Stilbite,
205	ERYTHRITE	Vivianite	Red, lavender-blue	1.5 - 2.5	3.07	Transparent to Translucent	Uncommon	Germany, France, USA, Iran, Morocco.	Hydrous Cobalt Arsenate	An arsenate mineral. Nickel substitutes iso-morphically for cobalt; admixtures of zinc, magnesium, and iron are also observed. It is encountered primarily in the form of crusts, concretions, and earthy aggregates.
206	ESCOLCITE
207	EUCLASE	Euclase	Colorless, sea-green, light blue, dark blue	7½	3.1	Transparent	Uncommon	Brazil, Russia, Zimbabwe, Tanzania and Zaire	Hydroxyy silicate of beryllium and alluminum	Euclase crystals are noted for their blue color, ranging from very pale to dark blue. The mineral may also be colorless, white, or light green. Euclase is difficult to cut and polish because of its perfect cleavage.
208	EUDIALYTE	Silicate	Pink-red, yellow-brown, Violet	5.0 - 6	2.74 - 3.10	Opaque	Uncommon	Julianehaab district of Greenland	Sodium Calcium Cerium Iron Manganese Zirconium Silicate Hydroxyide Chloride	Eudialyte is a somewhat rare, red silicate mineral, which forms in alkaline igneous rocks, such as nepheline syenites. Its name alludes to its ready solubility in acid.
209	EUXENITE	Oxide minerals	Black, green, brown	5½ - 6½	5.3 - 5.9	Opaque	Uncommon	Norway, Russia, Sweden, Brazil, US	Yttrium Calcium Erbium Lanthanum Cerium Uranium Thorium Niobium Tantalum Titanium Oxide	Euxenite is used as an ore of the rare earth elements it contains. Rare large crystals have also been used in jewelry
210	FACTORY / INDUSTRY									The aggregate of manufacturing or technically productive enterprises in a particular field, often named after its principal product, in this case gemstones and minerals
211	FAIRY STONE
212	FELDSPAR	Feldspar	White, grey, blue, green, red	6 - 6.5	2.6 - 2.65	Transparent to Opaque	Common	US, Brazil, India, Kenya, Madagascar, Namibia, Russia	Potassium Aluminum Silicate	Feldspar is a common raw material in the production of ceramics and geopolymers. Feldspars are used for thermo luminescence dating and optical dating in earth sciences and archaeology
213	FERBERITE	Wolframite	Black, dark brown, metallic grey	4 - 4½	7.58	Opaque	Uncommon	Greenland, Hungary, India, Kazakhstan, Mongolia, Peru, Romania, Rwanda, Thailand	Iron Manganese Tungstates	Ferberite tends to be black colored, with a black streak, is opaque with a nearly submetallic luster, is denser, has crystals with a different elongation and can be weakly magnetic.
214	FERROMETEORITE (IRON METEORITE)	Silicate minerals Asteroids	Metallic grey, light and dark brown,	4.5	3.21-3.40	Opaque	Uncommon	Worldwide	Iron Oxide	A meteorite is a natural object originating in outer space that survives an impact with the Earth's surface. While in space it is called a meteoroid.
215	FILIGREE									Filigree is a delicate kind of jewellery metalwork, usually of gold and silver, made with tiny beads or twisted threads, or both in combination, soldered together or to the surface of an object of the same metal and arranged in artistic motifs.
216	FIRE OPAL									Please see Opal
217	FLINTSTONE	Sedimentary	Dark grey, black, green, white, brown	7	2.9 - 5.9	Opaque	Very Common	Worldwide	Silicon Dioxide	Technically a rock, not a mineral, being composed largely of tiny grains of quartz or chalcedony. It is usually rather pure, with few other minerals involved, often dark.
218	FLUORAPORHYLLITE	Silicates	Colorless, white, gray, green, brown. Rarely pink, purple, red, or orange	4.5 - 5	2.3 - 2.4	Transparent to translucent	Common	India, USA, South Africa	Hydrous calcium potassium fluoro-hydroxyl-silicate	Fluorapophyllite can be a beautiful mineral, forming in lustrous, transparent crystals that are well-formed and occasionally very large. Though it is found worldwide in volcanic zeolite environments,
219	FLUORESCENT STONE	Fluorite	Varies	4 - 7	Varies	Translucent to Opaque	Common	Worldwide	Calcium Fluoride	The minerals in some types of stone have properties which cause them, under certain conditions, to glow or fluoresce. This property can sometimes be beneficial. When searching for the minerals using ultraviolet light these stones will stand out from the other rocks.
220	FLUORITE	Fluorite	Purple, blue, green, yellow, colorless, brown, pink, black, red-orange	4	3.00 - 3.25	Transparent to Translucent	Very Common	Germany, Argentina, Burma, England, France, Namibia	Calcium Fluoride	Fluorite is a very popular mineral, and it naturally occurs in all colors of the spectrum. It is one of the most varied colored minerals in the mineral kingdom, and the colors may be very intense and almost electric. Blue John is also a very popular form of Fluorite.
221	FLUORITE W/ CHALCOPYRITE									Please see Fluorite and Chalcopyrite
222	FLUORITE W/ PYRITE									Please see Fluorite and Pyrite
223	FORSTERITE	Olivine	Colorless, Green, Yellow, Yellow green, White	6-7	3.21 - 3.33	Transparent	Common	Somma, Vesuvius, Italy	Magnesium silicate	Forsterite is associated with igneous and metamorphic rocks and has also been found in meteorites.
224	FOSSIL	Organic Amber	Black, brown, grey, white	Varies	Varies	Opaque	Uncommon	USA, Antarctica, Australia, Libya, Saudi Arabia	Varies	Fossils are the preserved remains or traces of animals, plants, and other organisms from the remote past.
225	FOSSIL CORAL									Please see coral
226	FUCHSITE	Fuchsite	White, grey, silver	2 – 2.25	2.76 - 3	Opaque	Uncommon	India (Nellore)	Potassium Aluminum Silicate Hydroxyide Fluoride	Fuchsite is the most common mica, found in granites, pegmatite’s, gneisses, and schist’s, and as a contact metamorphic rock or as a secondary mineral resulting from the alteration of topaz, feldspar, kyanite, etc.
227	FUCHSITE W/ KYANITE									Please see Fuchsite and Kyanite
228	GADOLINITE	Nesosilicate	Brown, Green, Green black, Light green, Black	6.5 - 7	4 - 4.5	Transparent to Opaque	Rare	Sweden, Norwary, Austria, China	Yttrium	Gadolinite-(Y) is a somewhat rare mineral, but does come in some attractive crystals that collectors desire. It forms prismatic, nearly diamond-shaped cross-sectioned crystals, usually with a green color and a nice luster.
229	GAGATE	Fossil	Jet Black, metallic dark brown.	2.5 – 4	1.30 – 1.35	Opaque	Uncommon	Egypt, Rome, Greece, Serbia	Carbon, Hydrogen and Oxygen	Gagate is a carbon fossil, compact and very light. It is a lustrous black stone. Another name for Gagate is Black Amber or Jet.
230	GILLA MONSTER
231	GALENA	Galena	Lead-grey	2½	7.57	Opaque	Common	Angola, Belgium, Bolivia, Morocco, Denmark	Lead sulfide	One of the earliest uses of galena was as kohl, which in Ancient Egypt, was applied around the eyes to reduce the glare of the desert sun and to repel flies, which were a potential source of disease.
232	GALLITE	Igenous Rock	Grey	3 - 3.5	4.1 - 4.3	Opaque	Common	Bulgaria, Nambia, Cuba	Copper iron sulfide	A tetragonal-scalenohedral gray mineral containing copper, gallium, and sulfur.
233	GARCIT AGATE									Please see Agate
234	GARNET	Garnet Grossular	Wine red, red-brown, yellow, green, black	6½ - 7½	4.2	Transparent to Translucent	Common	India, USA, Sri Lanka, Madagascar and Africa	Calcium Aluminum Silicate	Garnet sand is a good abrasive and a common replacement for silica sand in sand blasting. Mixed with very high pressure water, garnet is used to cut steel and other materials in water jets. Pure crystals of garnet are used as gemstones.
235	GARNET IN QUARTZ									Please see Garnet and Quartz
236	GARNIERITE	Serpentine	Apple green, light brown	2½-3	2.3	Translucent	Common	Brazil, Dominican Republic, Japan, New Caledonia, Turkey	Hydrous Nickel Magnesium Silicate	Garnierite is a general name for a green nickel ore which is found in pockets and veins within weathered and serpentinized ultramafic rocks.
237	GARTRELLITE	Tsumcorite	Greenish yellow	4.5	5.4	Transparent		Western Australia, Australia
238	GETCHELLITE	Sulfide mineral	Blood red, dark red, purple red	1½ - 2	3.92	Translucent to Opaque	Uncommon	Kyrgyzstan, Russia, USA, Japan, Azerbaijan	Arsenic And Antimony Sulfides	Getchellite is a rare sulfide of arsenic and antimony.
239	GLASS	Natural Glass	Dark Red, Dark Red, Sometimes With A Purple To Green Iridescent Tarnish	5 - 6½	2.6	Transparent	Very Common	Kyrgyzstan, Russia, Usa, Japan, Azerbaijan	Fused Silicon Dioxide	Glass is an amorphous (non-crystalline) solid material that exhibits a glass transition, which is the reversible transition in amorphous materials (or in amorphous regions within semi crystalline materials) from a hard and relatively brittle state into a molten or rubber-like state.
240	GLAUCOPHANE	Amphibolite	Gray, blue-black, lavender blue	6 - 6.5	3 - 3.2	Opaque	Very Common	Common Worldwide	Sodium Magnesium Iron Aluminum Silicate Hydroxyide	Glaucophane is a common amphibole mineral, a sodium, magnesium, and aluminum silicate that occur only in crystalline schist’s formed from sodium-rich rocks by low-grade metamorphism characteristic of subduction zones.
241	GOETHITE	Iron oxide	Yellow, red to dark brown	5 - 5.5	3.3 - 4.3	Translucent to Opaque	Uncommon	USA, Czech Republic, Germany, South America, Italy, UK	Hydrated Iron Oxide	Goethite named after the German polymath Johann Wolfgang von Goethe (1749–1832), is an iron bearing oxide mineral found in soil and other low-temperature environments.
242	GOGUNJULA
243	GOLD	Copper	Metallic golden, Brass yellow, bright golden	2½ - 3	15 - 19.3	Opaque	Common	South Africa, Brazil, Russia, USA	Gold	Gold is a chemical element. It is a highly sought-after precious metal in jewelry, in sculpture, and for ornamentation since the beginning of recorded history.
244	GOLDSTONE		Reddish brown	5.5	2.5 - 2.8	Opaque	Very Common	Worldwide	Copper Oxide	Goldstone is man made. Some speculate it was discovered by accident when alchemists were trying to create man made gold. Goldstone is created of brown glass with copper oxide added.
245	GOOSECREEKITE	Zeolite	White, Pink and Red	4.5	2.21	Transparent	Uncommon	India, USA	Calcium Aluminium Silicate Hydroxide	Goosecreekite is one of the rarer zeolites and one of the most usually named minerals in the world. It forms irregular aggregates and prismatic crystals that are found in the vesicles or bubbles of volcanic rock as are most other zeolites.
246	GOSHENITE		Colorless, White	7.5 - 8	2.8	Transparent to translucent	Common	Brazil, China, Canada, Mexico, Russia, Northern Europe, East Africa, South Africa, Asia and Colombia		goshenite The name for this gemstone derives from Goshen Massachusetts, which was one of the first areas to discover the gem. Today it can be found in several countries, but most are mined in Brazil, America and Canada.
247	GRANDIDIERITE	Nesosilicate	Bluish green	7½	2.96	Transparent, Translucent	uncommon			Grandidierite is an extremely rare mineral and gem that was first discovered in 1902 in southern Madagascar. The mineral was named in honor of French explorer Alfred Grandidier (1836–1912) who studied the natural history of Madagascar.
248	GRANITE	Feldspar	Pink, grey, varies	5-7	2.65 - 2.75	Opaque	Very Common	Common Worldwide	Igneous Rock	Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite has a medium to coarse texture, occasionally with some individual crystals larger than the groundmass forming a rock known as porphyry.
249	GREEN BERYL									Please see Beryl
250	GREEN QUARTZ									Please see Quartz
251	GREENALITE	Kaolinite-Serpentine	Bright green, pale green, brown	2.5	2.85-3.15	Opaque	Common	Australia, Canada, China, Germany, USA, Worldwide	Hydroxyy Silicate of Magnesium with Clay	Greenalite was first described in 1903 for an occurrence in the Mesabi Range near Biwabik, St. Louis County, Minnesota and named for its green color. It occurs as a primary phase in banded iron formations.
252	GREENSTONE	chlorite,								Greenstone is a common generic term for valuable, green-hued minerals and metamorphosed igneous rocks and stones which early cultures used in the fashioning of hardstone carvings such as jewelry, statuettes, ritual tools, and various other artifacts.
253	GREEN SWISS OPAL									Please see Opal
254	GROSSULAR	Garnet Grossular/ Intermediate varieties	Colorless, green, yellow, brown	6½ - 7	3.57 - 3.73	Translucent to Opaque	Common	Canada, Kenya, Mali, Pakistan, Russia, Sri Lanka, South Africa, Tanzania, United States (Vermont)	Calcium Aluminum Silicate	Grossular (also known as grossularite), like other garnets, forms rounded crystals with 12 rhombic or 24 trapezoidal faces or combinations of these and some other forms. This crystal habit is classic for the garnet minerals.
255	GROSSULAR GARNET									See Grossular and Garnet
256	GUNMETAL	Bronze Metal	Dark grey	4 - 4.5	8.7	Opaque	Uncommon	USA	Copper, Tin, Lead Zinc	Gunmetal was originally used chiefly for making guns, and was eventually superseded by steel. Gunmetal casts and machines well and is resistant to corrosion from steam and salt water and is used to make steam and hydraulic castings, valves, and gears, and also statues and various small objects.
257	GYPSUM	Gypsum	White, yellow, pink, blue, colorless	2	2.20 - 2.40	Transparent to Opaque	Very Common	Algeria, Angola, USA, Vanuatu, Venezuela, Zimbabwe	Hydrated Calcium Sulphate	Gypsum is very sensitive to heat. It is rock-forming; compared to alabaster.
258	GYROLITE	Phyllosilicates	White to Green	3 - 4	2.3	Transparent to Translucent	Uncommon	India, Ireland, USA	Sodium Calcium Aluminiumsilicate Hydroxide	Gyrolite often forms nodular aggregates. These aggregates can appear glassy, dull or even fiberous. Unlike other similar looking minerals (such as prehnite or smithsonite), gyrolite usually forms individual nodules as opposed to botryoidal or crustal growths. The aggregate nodules can often accompany many fine and rare minerals such as apophyllite, okenite and many of the zeolites. Much gyrolite forms inside of volcanic bubbles called vesicles and can only add another element to the surreal "landscape" inside.
259	HACKMANITE	Sodalite	Pale to deep violet, grayish or greenish-white	5.5 - 6	1.48	Translucent to Opaque	Uncommon	Canada, Greenland Burma, Russia, USA	Sodium Aluminum Silicate Chloride	Hackmanite is an important variety of sodalite exhibiting tenebrescence. When hackmanite from Quebec or Greenland is freshly quarried, it is generally pale to deep violet but the colour fades quickly to greyish or greenish whites a violet to pink-red colour in sunlight.
260	HALITE	Halide	Colorless, white, yellow, red, purple, blue	2½	2.168	Transparent to Translucent	Very Common	Azerbaijan, Belarus, Colombia, Denmark, Jordan, Kenya, Netherlands	Sodium Chloride	Halite is commonly known as rock salt. Halite forms isometric crystals. The mineral is typically colorless to yellow, but may also be light blue, dark blue, and pink depending on the amount and type of impurities.
261	HAUYNE	Sodalite	Blue, white, grey, yellow, green, pink	5 - 6	2.4 - 2.9	Translucent to Opaque	Common	Canary Islands, Germany, USA, Italy	Sodium Calcium Aluminum Silicate Sulfur Sulfate Chloride	Hauyne, haüyne or hauynite was first described in 1807 from samples discovered in Vesuvian lavas in Monte Somma, Italy, and was named in 1807 by Brunn-Neergard for the French crystallographer René Just Haüy (1743–1822).
262	HEDENBERGITE	Metamorphic Rock	Green to dark green, brownish-green, brown, gray, black	5 - 6	3.3 - 3.6	Opaque	Common	Italy, Sweden, Russia, Australia	Calcium magnesium silicate	Hedenbergite forms a series with Diopside, the magnesium equivalent of Hedenbergite, and may be partially replaced by it. Diopside and Hedenbergite can even occur together in a single crystal, with a core of Hedenbergite and outer zone of Diopside. Hedenbergite is often confused and misidentified as both Diopside and Augite.
263	HELIODOR	Beryl	Gold-yellow, yellow-green, yellow, pink, colorless	7.5 - 8	2.63 - 2.92	Transparent	Common	Namibia, Nigeria, Norway, Pakistan, Russia, Ukraine	Beryllium Aluminum Sillicate	Heliodor is a golden yellow gem variety of Beryl.
264	HEMATITE	Hematite	Black, black-grey, brown-red	5½ - 6½	5.12 - 5.28	Opaque	Very Common	England, Mexico, Brazil, Australia, United States and Canada	Iron Oxide	Hematite is a mineral, colored black to steel or silver-gray, brown to reddish brown, or red. It is mined as the main ore of iron. While the forms of hematite vary, they all have a rust-red streak. Hematite is harder than pure iron, but much more brittle.
265	HEMIMORPHITE	Zinc and Lead	White, Blue, Green	4.5-5	3.5	Translucent to Opaque	Uncommon	Siberia, Austrilia, USA, Germany	Zinc Silicate	Hemimorphite, is a sorosilicate mineral which has been historically mined from the upper parts of zinc and lead ores. It was often assumed to be the same mineral as smithsonite, and both were classed under the same name of calamine.
266	HETEROSITE	Orthorhombic	Purple black, also deep rose to reddish purple	4 - 4.5	3.4	Opaque	Uncommon	USA, Germany, Finland	Iron Phosphate	Heterosite is a series between Heterosite and Purpurite. The species of this series are secondary minerals formed by oxidation of Triphylite and Lithiophilite through the intermediate stage of Ferrisicklerite and Sicklerite.
267	HETIAN JADE									Jade form Hetian in Xinjiang, China. See Jade.
268	HEULANDITE	Zeolite	Colorless, pink, red, grey, yellow, green, white	3 - 3½	2.1 - 2.2	Transparent	Common	Brazil, China, Denmark, Guam, India, Kazakhstan, Morocco, Nicaragua	Hydrated Calcium Sodium Aluminum Silicate	Heulandite is a white, grey, red, or brown zeolite mineral that consists essentially of hydrated calcium Aluminum silicate in the form of elongated tabular crystals.
269	HIDDENITE	Spodumene	Yellow-green, emerald-green	6½ - 7	3.15 - 3.21	Transparent	Uncommon	Burma, Brazil, Madagascar and United States	Lithium Aluminum Silicate	Hiddenite is a pale-to-emerald green variety of spodumene that is sometimes used as a gemstone.
270	HILUTITE	Garnet Zircon Goethite Quartz	Green, light brown	6 - 7	2.65 - 4.3	Translucent to Opaque	Common	Germany, Lithuania , England, Denmark, France, Brazil or Russia		Hilutite was first showcased to the world in April 2009. It is an amazing combination of the minerals Garnet, Zircon, Goethite and Quartz.
271	HIMALAYAN STONE
272	HOLLANDITE	Hollandite	Grey-Black, Silver-Grey	4 - 6	5.05	Translucent to Opaque	Common	India, Australia, Austria, France, Germany, Slovakia, USA	Barium manganese oxide hydrate	A monoclinic-prismatic white mineral containing aluminum, barium, iron, lead, manganese, oxygen, silicon, and sodium.
273	HORNBLENDE RUBY									Please see Ruby
274	HORNSTONE									See Banded Hornstone
275	HOWLITE	Silicate	White with gray to black streaks	3.5	2.5 - 2.6	Translucent to Opaque	Common	Nova Scotia, Canada, USA,	Calcium Boro-silicate Hydroxide	Howlite, which is named for its discoverer Henry How (a Nova Scotia geologist), is one of those minerals that is more famous for imitating another mineral. In this case the other mineral is turquoise, a phosphate gemstone. Although howlite is always white or gray, it can accept dyes fairly easily and be dyed a turquoise blue.
276	HUBNERITE	Oxide	Yellowish brown to reddish brown, blackish brown, black; Deep red internal reflections in reflected light	4 - 4.5	7.12 - 7.18	Transparent to Translucent	Common	China, Bolivia, USA	Manganese Tungstate	Huebnerite is the manganese-rich end member of the Wolframite series. It is not always distinguished individually and is sometimes just classified as Wolframite.
277	IDOCRASE	Idocrase	Brown, yellow, brown-black, light green, blue-green white, red, violet	6.5	3.32 - 3.43	Transparent to Translucent	Uncommon	Italy	Complex Calcium Aluminum Silicate	Vesuvianite, also known as Idocrase, is a green, brown, yellow, or blue silicate mineral. Vesuvianite occurs as tetragonal crystals in skarn deposits and limestones that have been subjected to contact metamorphism.
278	IKRANITA									Please check granite.
279	ILMENITE	Ilmenite	Black, dark grayish-black, brownish-black, dark reddish-brown	5-6	4.68 - 4.76	Opaque	Common	Southern Urals, Urals Region, Russia	Iron titanium oxide	Ilmenite is one of the most significant ores of the metal titanium. It is mined as an important industrial mineral in several deposits throughout the world. Many of those deposits are in heavy placer sands. Ilmenite is very similar in structure to Hematite,
280	IMPERIAL TOPAZ	Topaz	Golden yellow	8	3.49 - 3.57	Transparent	Uncommon	Germany, Norway, Pakistan, Italy, Sweden, Japan, Brazil	Hydroxyy silicate of Aluminum with fluorite and iron	Imperial topaz is yellow, pink(rare, if natural) to slightly pinkish-orange to reddish-orange. Some imperial topaz can fade on exposure to sunlight for an extended period of time.
281	INDICOLITE - TOURMALINE	Tourmaline	Green, red-pink, blue, orange, yellow, colorless	7	2.98 - 3.2	Transparent	Uncommon	Brazil, Austria, France, Germany, Hungary, Italy, Mexico	Sodium Lithium Aluminum Boro-Silicate Hydroxyide	Indicolite is the blue color variety of the tourmaline mineral elbaite. Its typical color is a more deeper almost neon blue than other blue gems such as aquamarine and blue topaz.
282	INESITE	Silicates	Rose-red, pink, orange-pink, orange-red-brown	5.5 - 6	3.03 - 3.04	Translucent	Common	England, Austrialia, China, Germany, Japan, USA	Hydrous calcium manganese silicate	Inesite is an uncommon but appealing mineral that forms in attractive pink colors. Its crystals often have a very characteristic, chisel-shaped termination on one of the crystal angles. Inesite is likely named for the Greek term ines,
283	IOLITE	Iolite	Grey, blue, blue-violet, green, yellow-brown, colorless	7 - 7½	2.6 - 2.66	Transparent to Translucent	Common	Brazil, Sri Lanka, Myanmar, India, Madagascar, Spain	Complex Silicate of magnesium, aluminum and iron	Iolite is also know as cordierite. Catalytic converters are commonly made from ceramics containing a large proportion of cordierite.
284	IRON METEORITE	Iron	Metallic silver-gray, red-brown	4½	7.3 - 7.87	Opaque	Very Common	Chile, France, Hungary, India, Niger, Norway, Oman, Poland, Tajikistan	Iron	Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element (by mass) forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust.
285	JADE	Jade	Gree, lavender, red, yellow, white, black	6½ - 7	3.30 - 3.38	Translucent to Opaque	Uncommon	Canada, China, USA, Burma, Vietnam	Sodium Aluminum Silicate	Jade is an ornamental stone. The term jade is applied to two different metamorphic rocks that are made up of different silicate minerals: Nephrite and Jadeite.
286	JADEITE	Jade	Apple-green, green-white, purple-blue, blue-green	6½ to 7	3.25 - 3.35	Translucent to Opaque	Uncommon	Burma (Myanmar)	Sodium Aluminum Silicate	Jadeite is a pyroxene mineral with composition NaAlSi2O6. Jadeite forms solid solutions with other pyroxene endmembers such as augite and diopside, aegirine, and kosmochlor.
287	JASPER	Chalcedony	Red, yellow, brown, green, blue	6½ - 7	2.58 - 2.91	Opaque	Common	Egypt, Australia, Brazil, India, Canada, Kazakhstan, Madagascar, Russia	Silicon Dioxide	The appeal of Jasper is its interesting color patterns and formations. Though it can be a solid color, it is most often mottled, spotted, ringed, or striped. Each Jasper has a unique color or pattern, lending this gemstone much variety. Jasper is an opaque form of Chalcedony.
288	JASPER WITH CHRYSOCOLLA									Please see Jasper and Chrysocolla
289	JIMTHOMPSONITE		Colorless, Pink brown	2-2.5	3.03	Transparent	Very Common	Carlton Quarry (Carleton Talc Mine), Chester, Windsor Co., Vermont, USA	Magnesium iron silicate	Jimthompsonite is an inosilicate with a triple chain silicate backbone. Pyroxenes have a single chain, amphiboles have a double chain, and jimthompsonite and a few other minerals have even wider chains.
290	JULGOLDITE	Pumpellyite	Green Black	4.5	3.6	Translucent to Opaque	Common	India, Sweden, Germany, Italy	Calcium Iron Aluminosilicate	Julgoldite is a member of the pumpellyite mineral series, a series of minerals characterized by the chemical bonding of silica tetrahedra with alkali and transition metal cations. It has been recognized for its importance in low grade metamorphism.
291	KAILASH STONE
292	KASOLITE	Radioactive Mineral	Green, gray green, yellow, yellow brown, red-orange	4 - 5	5.83 - 6.5	Translucent to Opaque	Uncommon	Egypt, France, Gabon, Germany, Hungary, India, Italy	Hydrated Lead Uranyl Silicate	Kasolite is a natural radioactive mineral. Kasolite derives it's name from its main locality, Kasolo, Zaire, Kasolite can be found in world wide in uranium-bearing ores. Kasolite forms sheaves of divergent crystals, rivet washers, sea urchins and radiate aggregates fibrous.
293	KIMBERLITE	Peridotite	Blue, yellow, black, stone grey	10	2.5-3.1	Opaque	Uncommon	USA, South Africa,	Silicon Carbide (Chromium)	Kimberlite is a type of potassic volcanic rock best known for sometimes containing diamonds. Kimberlite occurs in the Earth's crust in vertical structures known as Kimberlite pipes. Kimberlite pipes are the most important source of mined diamonds today.
294	KORNERUPINE	Borosilicates	Green, colorless, white, pink, yellow or brown	6 - 7	3.3	Transparent to Translucent	Uncommon	Greenland, Sri Lanka, Madagascar, Tanzania	Magnesium aluminum borate silicate	Kornerupine is a rare transparent to translucent gemstone named in honour of Andreas Nikolaus Kornerup a Danish naturalist, artist and explorer.
295	KOTOITE	Dolomite	Colorless, White	6.5	3.04	Opaque	Uncommon	North Korea	Calcium Magnesium Carbonate	Kotoite, a borate anhydrous magnesium owes its name to Bundjiro Koto (1856 - 1935), a geologist Japanese professor at the ' University of Tokyo. It was first artificially synthesized before being found in nature.
296	KROHNKITE	Roselite	Blue, dark sky blue, green-blue, yellow-green	2½ – 3.0	2.06 - 2.9	Transparent to Translucent	Uncommon	Chile	Hydrated Sodium Copper Sulfate	Kröhnkite is a rare copper sulfate mineral named after B. Kröhnke who first researched it.
297	KUGEL FOSSIL
298	KUNZITE	Spodumene	Pink-violet, light violet	6½ - 7	3.15 - 3.21	Transparent	Uncommon	Brazil, Afghanistan, Burma, Madagascar, Pakistan	Lithium Aluminum Silicate	Kunzite is a pink to lilac colored gemstone, a variety of spodumene with the color coming from minor to trace amounts of manganese. Some (but not all) kunzite used for gemstones has been heated to enhance its color. It is also frequently irradiated to enhance the color.
299	KYANITE	Kyanite	Blue, blue-green, brown, colorless	Along axes 4-4½ across 6-7	3.53 - 3.70	Transparent to Translucent	Common	Burma, Brazil, Kenya, Austria, Switzerland, Zimbabwe	Aluminum Silicate	Kyanite is used primarily in refractory and ceramic products, including porcelain plumbing fixtures and dishware. It is also one of the index minerals that are used to estimate the temperature, depth, and pressure at which a rock undergoes metamorphism.
300	LABRADORITE	Feldspar Plagioclase	Dark-grey, grey-black, brown	6 - 6 1/2	2.65-2.75	Opaque	Very Common	Canada, Australia, Madagascar, Mexico, Russia and United Stated	Sodium calcium aluminum silicates	Labradorite is a plagioclase feldspar. Used for bead necklaces, brooches ring, and ornamental objects. Colorless and yellowish-brown transparent labradorites are cut with facets. Labradorite is a form of Spectrolite.
301	LACE AGATE	Chalcedony	White, grey, green, yellow, brown	6½ - 7	2.58 - 2.64	Opaque	Very Common	Angola, Armenia, Bulgaria, India, Jamaica, Panama, Papua New Guinea	Silicon Dioxide	Agate is a microcrystalline variety of quartz, chiefly chalcedony, characterized by its fineness of grain and brightness of color. Although agates may be found in various kinds of rock.
302	LANGITE	Monoclinic	Blue, greenish-blue	2.5-3	3.5	Translucent	Very Common	Fowey Consols, Tywardreath, Par Area, St Austell District, Cornwall, England, UK	Hydrated copper sulfate	Langite is a rare hydrated copper sulfate mineral, with hydroxyl, found almost exclusively in druses of small crystals. It is formed from the oxidation of copper sulfides, and was first described in specimens from Cornwall, England.
303	LAPIS LAZULI	Lapis Lazuli	Lazur blue, violet, green-blue	5 - 6	2.50 - 3.00	Opaque	Uncommon	Afghanistan, Russia, Chile, Angola, Burma, Canada, Pakistan	Sodium Calcium Aluminum Silicate Sulfur Sulfate	Lapis lazuli was already used in prehistoric times for jewelry. During the Middle Ages, it was also used as a pigment to produce aquamarine. Today it is used for ring stones and necklace as well as sculptures, vases and other ornamental objects.
304	LARIMAR	Pectolite	Light-blue, green-blue	5 - 7	2.84 - 2.90	Opaque	Uncommon	Dominican Republic	Sodium silicate	Larimar was originally discovered in 1916 by a Spanish priest who reported the discovery but no mining was done. It was determined by geologists that larimar is a rare form of blue pectolite.
305	LAUMONTITE	Zeolite	Colorless, pink, white, grey, yellow, brown, golden brown	3½ - 4	2.23 - 2.41	Opaque	Very Common	Denmark, Ecuador, Fiji, France, Hungary, India, Nicaragua, Sweden, Turkey, UK	Hydrated calcium aluminum silicate	A mineral, of a white color and vitreous luster. It is a hydrous silicate of alumina and lime. If exposed to the air, it loses water, becomes opaque, and crumbles.
306	LAVA STONE	Volcanic	Dark to light brown, stone grey	6	2.8	Opaque	Very Common	Worldwide	Mostly silicon dioxide with large amounts of impurities	A Lava Stone (often shortened to volcanics in scientific contexts) is a rock formed from magma erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin.
307	LAVENDER QUARTZ	Quartz	White, grey, green, yellow, brown	6½ - 7	2.58 - 2.64	Transparent to Translucent	Very Common	Germany, Hungary, Ireland, Isle Of Man, Italy, Japan, Madagascar, Kazakhstan, Namibia, Morocco	Silicon Oxide	Quartz belongs to the rhombohedral crystal system. The ideal crystal shape is a six-sided prism terminating with six-sided pyramids at each end. In nature quartz crystals are often twinned, distorted, or so intergrown with adjacent crystals of quartz or other minerals.
308	LAZULITE	Lazulite	Dark blue to blue-white, green-blue	5 - 6	3.04 - 3.14	Transparent to Translucent	Uncommon	Angola, Bolivia, Brazil, India, Madagascar, Austria, Sweden and United States	Hydroxyy phosphate of Aluminum, mahnesium and iron	Lazulite forms by high grade metamorphism of high silica quartz rich rocks and in pegmatites. It is considered a semi-precious gemstone. It is often confused with lazurite, lapis lazuli or azurite.
309	LAZURITE	Tectosilicate Sodalite	Deep blue, azure, violet-blue, greenish blue	5 - 5.5	2.38 - 2.45	Translucent to Opaque	Uncommon	USA, Afghanistan, Burma, Canada, Chile	Hydroxyy phosphate of Aluminum, mahnesium and iron	Lazurite is a product of contact metamorphism of limestone and typically is associated with calcite, pyrite, diopside, humite, forsterite, hauyne and muscovite
310	LINARITE	Linarite-Chenite	Deep azure blue	2.5	5.3	Transparent to Translucent	Uncommon	Plateau, Spain	Basic sulfate of lead and copper	Linarite is a somewhat rare, crystalline mineral that is known among mineral collectors for its unusually intense, pure blue color.
311	LEAD	Copper group	Metallic grey, blue-white, grey-black	1½	11.37	Opaque	Common	Ethiopia, Greenland, Mexico, Mongolia, Poland, Sweden	Lead	Lead is a soft, malleable poor metal, also considered to be one of the heavy metals. Lead has a bluish-white color when freshly cut, but tarnishes to a dull grayish color when exposed to air.
312	LEAD SULFIDE	Copper group	Colorless, white, tinted grey, yellow, green, blue, colorless	2½ - 3	6.37 - 6.39	Opaque	Common	Armenia, Cuba, France, Japan Ghana, India, Iran	Lead Sulphate	Lead sulphide (also spelled sulfide) is most often purified from the mineral galena. It is synonym of Anglesite.
313	LEGRANDITE	Arsenate	Bright yellow, wax-yellow, colorless	4.5 - 5	3.98 - 4.01	Translucent to Opaque	Uncommon	Germany, Greece, Mexico, USA	Zinc Arsenate	Legrandite was named for a Belgian mine engineer known only as a Mr. Legrand, who was the first to collect the mineral. An uncommon mineral, occurs in oxidized zinc-arsenic bearing deposits, and can be found, albeit rarely, in granite pegmatites.
314	LEMON QUARTZ									Please see Quartz
315	LENGENBACHITE	Sulfides	Steel-grey, black, grey-blue	1 - 2	5.8 - 5.85	Translucent to Opaque	Uncommon	Switzerland	Lead Arsenic Antimony Sulfide	Lengenbachite from its only known occurrence at Binntal in the Swiss Dolomites, was described by R.H. Solly (1905). The mineral is layered, with a perfect cleavage and is relatively malleable.
316	LEPIDOLITE	Silicates	Violet, pale pink, white, grey, yellow	2.5	2.76	Opaque	Uncommon	Brazil; Ural Mountains, Russia; several African localities and California, USA	Potassium lithium aluminum silicate Hydroxyide fluoride	Lepidolite is an uncommon mica and has only in the past decade become available on the mineral market in large quantities. Lepidolite is an ore of lithium and forms in granitic masses that contain a substantial amount of lithium.
317	LEUCITE	Tectosilicates	Colorless, white, yellow	5 1/2 - 6	2.45 - 2.50	Opaque	Very Common	Brazil, Cameroon, France, Czech Republic, Germany, Greenland, Hungary, India	Potassium aluminum silicate	Leucite is a rock-forming mineral composed of potassium and Aluminum tectosilicate
318	LEVYNE	Zeolite	Brown and in many shades	4 - 4.5	2.09 -2.16	Transparent to Translucent	Uncommon	India, Iceland, Japan, Australia, USA	Calcium Sodium Potassium Aluminosilicate Hydrate	Levyne crystallizes in the Trigonal - Hexagonal Scalenohedral class. It typically occurs as radiating clusters or fibrous masses that are transparent to translucent in colors ranging from white through reddish and yellowish white to gray.
319	LIDDICOATITE	Tourmaline	Usually smoky brown, but also pink, red, green, blue, or rarely white	7.5	3.02	Transparent to Translucent	Uncommon	Canada, Madagascar	Calcium Lithium Aluminum Boro-Silicate Hydroxyide	Liddicoatite is an uncommon form of Tourmaline. It was not recognized as a separate Tourmaline species until 1977. Prior to that time, it was thought to be Elbaite.
320	LIGNITE	Coal	Brown-black	2½-4	1.03	Opaque	Common	Bolivia, Dominican Republic, Germany, Spain, Thailand, Turkey	Mainly Carbon (Mixed)	Lignite, often referred to as brown coal, or Rosebud coal by Northern Pacific Railroad, is a soft brown fuel with characteristics that put it somewhere between coal and peat.
321	LIMESTONE BRACHIOPODS	Calcite	Light yellow, light brown, pink, red	3 - 4	2.50 - 2.70	Opaque	Common	Biochemical Origin	Calcium Carbonate	Limestone is calcareous sedimentary rocks formed at the bottom of lakes and seas with the accumulation of shells, bones and other calcium rich goods. The organic matter upon which it settles in lakes or seas, are preserved as fossils.
322	LIMESTONE JURASSIC RED									Limestone is a sedimentary rock consisting of more than 50% calcium carbonate ( calcite - CaCO 3). There are many different types of limestone formed through a variety of processes. Limestone can be precipitated from water ( non-clastic, chemical or inorganic limestone).
323	LIMONITE	Amorphous, mineraloid	Light brown, brown, yellow-brown	4 - 5½	2.7 - 4.3	Opaque	Common	Europe, Mexico, Canada and northeastern USA	Iron Oxide	Limonite is an iron ore consisting of a mixture of hydrated iron(III) oxide-Hydroxyides in varying composition. Limonite is one of the two principle iron ores, the other being hematite, and has been mined for the production of iron since at least 2500 BCE.
324	LIROCONITE	Arsenate	Sky-blue, green, light blue	2 - 2½	2.9 - 3	Translucent to Opaque	Uncommon	Slovakia, Germany, USA, UK, Australia	Hydrated Copper Aluminum Arsenate Hydroxyide	Liroconite is a truly beautiful mineral with a typical bright blue color, a nice glassy luster and an interesting crystal habit. It forms from the oxidation of primary copper ores.
325	LIZARDITE	Serpentine	Bright green, yellow green, brown green	2-2.5	3.18 - 3.24	Translucent to Opaque	Uncommon	UK, Germany, Slovakia, USA, South Africa, Norway	Potassium Hydroxide	Lizardite belongs to the kaolinite-serpentinite group of minerals and is one of three minerals commonly referred to as ‘serpentine’. Lizardite is the most common of the three serpentine minerals and is typically found with brucite and magnetite.
326	LORANDITE	Sulfosalt mineral	Red, lead grey	2 - 2½	5.53	Transparent to Translucent	Uncommon	China, Republic of Macedonia, Russia, Switzerland, USA	Thallium Sulfarsenites	Lorandite occurs in low temperature hydrothermal associations. Occurs in gold and mercury ore deposits.
327	LUCKY STONE	Ear Bone/Ivory	White	2.5 - 3	1.67	Opaque	Uncommon	Canada		Lucky stone is actually the unique ear bone or otolith of a Freshwater Drum, commonly known as the Sheephead Fish. The Sheephead's otoliths are quite large and look almost polished and ivory-like.
328	LUNA STONE									See Moonstone
329	MAGNESITE	Carbonate	White or grey, also tinted yellow or brown	4 – 4.5	2.98 - 3.02	Transparent to Translucent	Common	Austria; Bahia, Brazil; Korea; China; California, USA	Magnesium Carbonate	Magnesite does not ordinarily form good crystals, but can make up a substantial portion of some rock types. It forms commonly from the alteration of magnesium-rich rocks during low grade metamorphism while they are in contact with carbonate-rich solutions.
330	MAGNETITE	Spinel	Iron black	5½ - 6½	5.175	Opaque	Uncommon	Japan, Ecuador, Finland, France, Germany, Greece, Greenland, India, Serbia, Thailand	Iron Oxide	Magnetite is the most magnetic of all the naturally occurring minerals on Earth, and naturally magnetized deposits of magnetite, or lodestone, was how ancient man first discovered the property of magnetism.
331	MALACHITE	Malachite	Light to black-green, banded	3 1/2 - 4	3.25 - 4.10	Opaque	Common	Zaire, Australia, Chile, Namibia, Zimbabwe, United States	Hydroxy of Copper Carbonate	Malachite was popular with the ancient Egyptians, Greeks and Romans for jewelry, amulets and as a powder for eye shadow, nowadays popular for jewelry and ornaments.
332	MANGANESE	Metal	Steel-grey	6½	7.01	Opaque	Common	Chile, USA	Manganese	It is found as a free element in nature (often in combination with iron), and in many minerals. As a free element, manganese is a metal with important industrial metal alloy uses, particularly in stainless steels.
333	MANGANOCALCITE	Calcite	Pink	3	2.69 - 2.71	Translucent to Opaque	Uncommon	Slovakia, Mexico, Bulgaria	Calcium Carbonate	Manganocalcite is a variety of calcite rich in manganese, which gives the mineral a pink color. Manganocalcite is sometimes confused with rhodochrosite.
334	MANGANOTANTALITE	Oxide minerals	Dark black, iron-black to dark brown, reddish brown	6 - 6.5	8	Opaque	Uncommon	Malawi, Namibia, Mozambique, Norway	Iron Manganese Tantalum Niobium Oxide	Manganotantalite is a form of iron-rich tantalite with characteristics similar to those of Tantalite.
335	MAPS / SURVEY									Mapping/Surveying is the technique, profession, and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them, commonly practiced by licensed surveyors.
336	MARBLE	Calcite	White, green, grey-brown, blue-grey	3	2.76	Opaque	Very Common	Afghanistan, Argentina, Austria, Canada, Norway, USA	Calcium Carbonate	Marble is the product of metamorphism on Limestone. Typically this metamorphic rock is composed primarily of carbonates, primarily Calcite (Calcium Carbonate).
337	MARCASITE	Sulfide mineral	Pale brass-yellow, tin-white	6 - 6½	4.887	Opaque	Common	USA, Mexico, Canada, Tanzania, China, India	Iron sulfide	The mineral marcasite, sometimes called white iron pyrite, is iron sulfide (FeS2) with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure.
338	MARIAM
339	MARIPOSA MARBLE	Calcite	White, green, grey-brown, blue-grey	3	2.76	Opaque	Very Common	Afghanistan, Argentina, Austria, Canada, Norway, USA	Calcium Carbonate	Marble is the product of metamorphism on Limestone. Typically this metamorphic rock is composed primarily of carbonates, primarily Calcite (Calcium Carbonate).
340	MARRA MAMBA	Oxides and Hydroxyides	Red, light to dark brown, with shades of orange	5 - 6	2.63 - 2.65	Opaque	Uncommon	South Africa, Namibia, Australia, India, Thailand	Iron Oxide	Marra Mamba forms when Quartz forms over existing bluish-gray Crocidolite. Crocidolite is a type of asbestos mineral, which means its composition is of fine, dense fibers. These fibers form in a parallel yet wavy orientation, and this causes the intriguing chatoyant effect exhibited. Marra Mama is another word for Tiger's Eye.
341	MAW SIT SIT	Maw-sit-sit	Light green, black	6 - 7	2.5 to 3	Opaque	Common	Myanmar	Aluminum Chromium Oxide	Maw-sit-sit is a chromium-rich metamorphic rock with brilliant emerald green blotches and bands interspersed with dark green-black blotches. It was first noted in the early 1960’s by the famed Swiss gemologist Eduard J. Gübelin during field investigations in Burma.
342	MEERSCHAUM	Sepiolite	White, light grey, light yellow	2 - 2.5	2.0 - 2.1	Opaque	Common	China, Greece, Hungary, Kenya, Malaysia, Norway, Turkey	Potassium aluminum silicate Hydroxyide fluoride	Meerschaum, also known as sepiolite, is a soft white mineral, often used to make smoking pipes. It is sometimes found floating on the Black Sea.
343	MELLITE	Tetragonal	Honey to wax yellow, brown to reddish, gray, seldom white	2-2.5	1.64	Transparent to Translucent	Common	Arten, Thüringen, Germany	organic minerals	It is a translucent honey-coloured crystal which can be polished and faceted to form striking gemstones. It crystallizes in the tetragonal system and occurs both in good crystals and as formless masses.
344	MERCURY	Metal	Tin white, silver, grey	Could not be measured	13.596	Opaque	Uncommon	Chile, China, France, Germany, Hungary, Italy, Japan, Mexico	Mercury	Mercury is officially classed as a mineral species for historical reasons, and also because it is distinctive in its chemical and physical properties. However, because it occurs as a liquid, it does not satisfy the normal criteria to be a valid mineral.
345	MESOLITE	Zeolite	Colorless, white, grey, yellow	5	2.26	Transparent to Translucent	Uncommon	Antarctica, Australia, France, Germany, Hungary, Italy, Nicaragua, Panama	Hydrated sodium calcium aluminum silicate	Mesolite is a popular zeolite mineral for mineral collectors and zeolite collectors in particular. Its radiating sprays of ice-clear acicular crystals are a hallmark of this mineral.
346	MESOTYPE	Natrolite	White, colorless, red, yellow, brown, green	5 - 5½	2.2 - 2.26	Transparent to Translucent	Uncommon	Austria, Azerbaijan, Cameroon, Chile, Guam, Lesotho	Hydrated sodium calcium aluminum silicate	Mesotype is a common and popular zeolite mineral. Its radiating sprays of ice clear acicular crystals are not exclusive to natrolite but they are a hallmark of this mineral.
347	METAL									A general name given to typically hard, shiny, malleable, fusible, and ductile minerals/gemstones, with good electrical and thermal conductivity.
348	METAMORPHIC ROCK	Varies	Varies	Varies	Varies	Opaque	Varies	Varies	Metamorphic Rock	Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means "change in form".
349	METAVAUXITE		white, light green	3	2.345	Transparent to Translucent				metavauxite Named in 1927 by Samuel George Gordon allusion to the chemical relationship to Vauxite.
350	METEORITE	Silicate minerals Asteroids	Orange, yellow, red, blue-green, black, purple	4.5	3.21-3.40	Opaque	Uncommon	Worldwide	Elemental Iron-nickel	A meteorite is a natural object originating in outer space that survives an impact with the Earth's surface. While in space it is called a meteoroid.
351	MICA	Mica	White, yellow, green, brown, silver	2-2.5	2.8	Translucent	Very Common	USA, South America, South Africa, Romania, Iran, Egypt	Potassium aluminum silicate Hydroxyide fluoride	The micas are an important group of minerals. They represent the classic phyllosilicate mineral and are usually the first minerals to be thought of from this subclass of the Silicates Class.
352	MICROCLINE	Feldspar	White, grey, grey-yellow, tan, salmon-pink, blue-green, green	6 - 6½	2.54 - 2.57	Translucent to Opaque	Very Common	China, Egypt, Finland, Guyana, India, Madagascar	Potassium Aluminum Silicate	Microcline is an important igneous rock-forming tectosilicate mineral. It is a potassium-rich alkali feldspar. Microcline typically contains minor amounts of sodium. Amazon stone, or amazonite, is a beautiful green variety of microcline.
353	MIMETITE	Pyromorphite	Pale-yellow, yellow-brown, orange, white, colorless	3½ - 4	7.24	Translucent to Opaque	Uncommon	Australia, Bulgaria, Greece, Mexico, Morocco, Namibia, Portugal, Sweden, Thailand	Lead arsenate chloride	Mimetite shares the same structure with apatite and occasionally crystals of the two will have similar shapes. It usually is found as a botryoidal crust, a sparkling cauliflower aggregation or as minute spike-like crystals.
354	MILLERITE		Pale brass-yellow to bronze-yellow, tarnishes to iridescenc	3 - 3.5		Opaque			nickel sulfide	Millerite is a common metamorphic mineral replacing pentlandite within serpentinite ultramafics. It is formed in this way by removal of sulfur from pentlandite or other nickeliferous sulfide minerals during metamorphism or metasomatism.
355	MINERAL COMPOUNDS / MIXTURES / ALLOYS									Non mineral general items
356	MINERAL SCIENCE									Non mineral general items
357	MINERS									Non mineral general items
358	MINING									Non mineral general items
359	MINING TOOLS									Non mineral general items
360	MOHAWKITE	Copper	Pale-brass yellow, silver-gold	3 - 3.5	8.07	Opaque	Uncommon	Keweenaw Peninsula of Michigan	Copper Arsenide	Mohawkite is a rare rock consisting of mixtures of arsenic and copper, usually in white quartz matrix. It is name after the Mohawk mine were it was found originally.
361	MOLDAVITE	Tektite	Black, green or colorless	5 - 6	2.5	Translucent to Opaque	Uncommon	Moldavia, Czech Republic, Austria, USA	Silica glass with impurities of magnesium	Moldavites are especially prized for their clarity and unique green color. Moldavites are found in a "splash field" centered around Moldavia in former Czechoslovakia and are believed to have come from a meteorite crater in Germany.
362	MOLYBDENUM	Metal	Metallic white, metallic silver	5.5	10.2	Opaque	Uncommon	United States, Canada, Chile, Russia, and China	Molybdenum Sulfide	Molybdenum is found in such minerals as wulfenite and powellite , the main commercial source of molybdenum is molybdenite. Molybdenum is mined as a principal ore, and is also recovered as a byproduct of copper and tungsten mining.
363	MONAZITE	Monazite	Red-brown, brown, pale yellow, pink, green, grey	5 - 5½	5 - 5.5	Translucent	Common	Bolivia, Cameroon, Finland, Mozambique, Oman, Pakistan, Paraguay	Rare earth phosphate	Monazite is a reddish-brown phosphate mineral containing rare earth metals and is an important source of thorium, lanthanum, and cerium. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite.
364	MONTANA AGATE									Please see Agate
365	MOHAWKITE	Silicate	Red, yellow, tan, white	6.5 - 7.0	2.58 - 2.91	Opaque	Uncommon	Kennedy Ranges near Gascoyne Junction in Western Australia	Silicon dioxide	Mookaite is a siliceous, comparatively hard, fine-grained, chert-like, and homogeneous sedimentary rock that is composed predominantly of the microscopic remains of radiolarians.
366	MOONSTONE	Feldspar Orthoclase	Colorless, yellow, pale sheen	6 - 6 1/2	2.56 - 2.59	Translucent	Very Common	Sri Lanka, Burma, Brazil, India, Madagascar	Sodium Calcium Aluminum Silicate	Moonstone's delicate beauty and its long heritage make it perhaps the most familiar gem quality member of the feldspar group. Moonstone is composed of two feldspar species, orthoclase and albite.
367	MORDENITE	Zeolite	Red-brown, brown, pale yellow, pink, grey	5 - 5½	2.1 - 2.15	Translucent to Opaque	Common	Brazil, Bulgaria, Costa Rica, China, France, Greece	Hydrated Calcium Sodium Potassium Aluminum Silicate	Mordenite is one of the most abundant zeolites in altered volcanic deposits; it is found in volcanic rock such as rhyolite, andesite, and basalt. It is associated with other zeolites such as stilbite and heulandite. It is also found in marine sediments.
368	MORGANITE	Beryl	Soft pink, violet, salmon	7.5 - 8	2.71 - 2.90	Transparent	Common	Afghanistan, Brazil, China, Madagascar, Mozambique, Namibia, Zimbabwe	Beryllium Aluminum Silicate	Morganite, also known as "pink beryl", "rose beryl", "pink emerald", and "cesian (or caesian) beryl", is a rare light pink to rose-colored gem-quality variety of beryl.
369	MOSS STONE	Chalcedony	Red to dark brown	5.5 - 6	1.98 - 2.05	Opaque	Very Common	Australia, USA,	Sodium Iron Magnesium Silicate Hydroxyide	Moss Stones are delicate gemstones. Their most significant vulnerability has to do with their water content. If a Moss Stone is allowed to dry, it will crack and fade.
370	MULTIPLE STONES									Mixture of stones
371	MUSGRAVITE		Gray-green, green	8-8.5	3.62 to 3.68	Transparent		Australia	Taaffeite	Musgravite or magnesiotaaffeite-6N’3S (chemical formula of Be(Mg, Fe, Zn)2Al6O12), is a rare oxide mineral. It is used as a gemstone. Its type locality is the Ernabella Mission, Musgrave Ranges, South Australia for which it was named.
372	MUSCOVITE	Mica	White, colorless, silver-white	2½	2.77 - 2.88	Translucent	Very Common	Angola, Burundi, Chile, Ecuador, Peru, Poland	Hydrous potassium aluminum silicate	Muscovite is the most common mica, found in granites, pegmatites, gneisses, and schists. It is in demand for the manufacture of fireproofing and insulating materials and to some extent as a lubricant.
373	NACRE									Nacre is found in some of the most ancient lineages of bivalves, gastropods, and cephalopods. However, the inner layer in the great majority of mollusc shells is porcellaneous, not nacreous.
374	NAMBULITE	Manganese	Reddish orange brown	6.5	3.51	Transparent to Translucent	Uncommon	Japan, Nambia, Italy	Manganese Iron Magnesium Calcium	Nambulite is formed from the reaction between a hydrothermal solution and rhodonite, and commonly creates veins in the host rock. Other than a collector’s gem, however, it has little economic value.
375	NAHCOLITE	Carbonate	White to colourless, may be grey to brown	2.5	2.21	Transparent to translucent	Common	ITALY		Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs.
376	NATROLITE	Zeolite	Colorless to White	5 - 5.5	2.2	Transparent to Translucent	Common	India, USA, Nova Scotia	Sodium Aluminosilicate Hydrate	Natrolite is a common and popular zeolite mineral. Its radiating sprays of ice clear acicular crystals are not exclusive to natrolite but they are a hallmark of this mineral.
377	NATURAL GAS									A mixture of hydrocarbon gases that occurs with petroleum deposits, principally methane together with varying quantities of ethane, propane, butane, and other gases, and is used as a fuel and in the manufacture of organic compounds.
378	NEBULA		White,Green					Mexico, USA		Nebula Stone is also called ‘The Birthstone of the Cosmos’ and holds a rare combination of Arfedsonite, Zircon, Calcite, Acmite, Anorthoclase, Riebeckite, Aegirine, Quartz, and many other minerals.
379	NELLITE		Yellow, Light orange.	4	5.88	Translucent		Laurion, Attica, Greece		Nellite is a massive silicate that forms where tiger eye and pietersite meet: it's like a blend of both. Nellite has the golden, translucent glow of tiger eye in quartz
380	NEPHRITE	Jade	Green, also other colors	6 - 6 1/2	2.90 - 3.03	Opaque	Uncommon	New Zealand, Australia, Brazil, China, Canada, Mexico, Zimbabwe, Taiwan, United States	Silicate of Calcium, magnesium and iron	Nephrite is dense, felt-like actionolite that is even tougher than jadeite. It uses as cabochons in other jewelry and for vases both decorative and religious.
381	NEPHRITE JADE									See Nephrite and Jade
382	NEPTUNITE	Silicate	Visually black, with very dark maroon highlights visible on some edges or in backlighting.	5 - 6	3.2 - 3.3	Opaque	Rare	USA, Russia, Canada	Silicate of potassium, sodium, lithium, iron, manganese, and titanium	Neptunite is a relatively recent mineral, having been first discovered only in the early 1900's. It is named after Neptunus, the Roman god of the sea, and its etymology is derived from its similarity to Aegrine, which was named after the Norse sea god.
383	NETROLITES									Please see Mesotype/Mesolite
384	NICCOLITE	Arsenide mineral	Pale copper red	5 - 5½	7.784	Opaque	Uncommon	Ghana, Greece, Greenland, Hungary, Iran, Morocco	Nickel arsenide	Niccolite or Nickeline is a mineral consisting of nickel arsenide, NiAs, containing 43.9% nickel and 56.1% arsenic.Small quantities of sulfur, iron and cobalt are usually present, and sometimes the arsenic is largely replaced by antimony.
385	NICKEL	Metal	White	3½	8.908	Opaque	Uncommon	Italy, Slovakia, Sweden, USA	Nickel	Nickel is a silvery-white metal with a slight golden tinge that takes a high polish. It is one of only four elements that are magnetic at or near room temperature. It belongs to the transition metals and is hard and ductile.
386	OBSIDIAN	Natural Glass	Black, grey, brown, green	5 - 5 1/2	2.35 - 2.60	Opaque	Uncommon	Ecuador, Indonesia, Iceland, Italy, Japan, Mexico and United States	Silicon Dioxide	Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. The silicas left over after most of the other elements and water have been used up are ejected or flow out and rapidly chilled at surface temperatures.
387	OCEAN WAVE AGATE									Please see Agate
388	OCEAN WAVE JASPER									Please see Jasper
389	OIL									Any of a number of viscous liquids with a smooth sticky feel. They are usually flammable, insoluble in water, soluble in organic solvents, and are obtained from plants and animals, from mineral deposits, and by synthesis.
390	OKENITE	Inosilicates	White to Yellow	4.5 - 5	2.3	Transparent to Translucent	Uncommon	India, Greenland, Chile, Ireland	Silicate Hydrate	Okenite is an unusual mineral. It frequently forms "cottonball" clusters where the crystals are so thin they look like tiny fibers. s.
391	OLENITE	Tourmaline	Light pink, blue, colourless	7	3.01	Translucent	Uncommon	Austria, Italy, Russia, USA	Aluminum-rich tourmaline	Olenite is a very Al-rich member of the Tourmaline Group. Named for the type locality area, an unspecified granite pegmatite on the small Olenii Ridge, Kola Peninsula, Russia.
392	OLIVINE	Silicate	Yellow-green, olive green, green-black, red-brown	6½ - 7	3.27 - 3.37	Translucent to Opaque	Very Common	Venezuela, Vietnam, Zimbabwe, Tanzania, Trinidad and Tobago, Uganda	Magnesium iron silicate	Olivines are an important rock-forming mineral group. Magnesium-rich olivines are abundant in low-silica mafic and ultramafic igneous rocks and are believed to be the most abundant constituent of the Earth’s upper mantle.
393	OMPHACITE JADE	Pyroxene	Dark to Pale Green	5 - 6	3.16 - 3.43	Opaque	Common	Austria, China, Germany, USA, Italy, Norway	Calcium Rich Silicate	Omphacite is a member of the pyroxene group of silicate minerals with a variably deep to pale green or nearly colorless variety of pyroxene.
394	ONYX	Chalcedony	Almost every color , shades of purple or blue	7	2.65	Translucent to Opaque	Very Common	Madagascar, Germany, Canada, Russia, UK	Calcium Carbonate	Onyx is a cryptocrystalline form of quartz. It is usually cut as a cabochon, or into beads, and is also used for intaglios and cameos, where the bands make the image contrast with the ground.
395	OPAL	Opal	Colorless, white, yellow, red, orange, green, brown, black, blue, pink	5½ - 6½	1.9 - 2.3	Transparent to Opaque	Very Common	Venezuela, Vietnam, India, Zimbabwe, Tanzania, Trinidad and Tobago, Uganda	Silica with Water	Opal is a silica mineral extensively used as a gemstone, a submicrocrystalline variety of cristobalite. In ancient times opal was included among the noble gems and was ranked second only to emerald by the Romans. It is a mineraloid gel which is deposited at a relatively low temperature
396	OPALITE	Opal	Colorless, white, yellow, red, orange, green, brown, black, blue, pink	2.5	1.2	Opaque	Very Common	Worldwide	Hydrated Silicon Dioxide	Opalite is a trade name for synthetic opalised glass and various opal simulants. It is also used to promote impure varieties of variously colored common opal.
397	ORBICULAR DIORITE	Plutonic	Black, grey	7	2.8 - 3.0	Opaque	Uncommon	Corsica, South Africa, North Carolina	Intermediate Intrusive Igneous Rock	An Orbicular Diorite is a variety of diorite which is characterized by orbicular structure. The grey matrix of the stone has the normal appearance of a diorite, but contains many rounded lumps 1 or 2 inches in diameter.
398	ORBICULAR DIORITE W/ HORNBLENDE	Plutonic	Black, grey	7	2.8 - 3.0	Opaque	Uncommon	Corsica, South Africa, North Carolina	Intermediate Intrusive Igneous Rock	An Orbicular Diorite is a variety of diorite which is characterized by orbicular structure. The grey matrix of the stone has the normal appearance of a diorite, but contains many rounded lumps 1 or 2 inches in diameter.
399	ORBICULAR GRANITE	Plutonic	Dark and light grey	2.5	2.65 - 2.75	Opaque	Uncommon	Finland and South Africa	Intermediate Intrusive Igneous Rock	Orbicular granite (also known as orbicular rock or orbiculite) is an uncommon plutonic rock type which is usually granitic in composition. These rocks have a unique appearance due to orbicules.
400	ORBICULAR RHYOLITE	Chalcedony	Light Brown, pink	6.5 to 7	2.4 - 2.6	Opaque	Common	Madagascar, Russia, USA	Extrusive Volcanic Rock	Orbicular Rhyolite is a variety of jasper which contains variably-colored orbs or spherical inclusions or zones. In highly silicified rhyolite or tuff, quartz and feldspar crystallize in radial aggregates of needle-like crystals which provide the basis or seed for the orbicular structure seen in this kind of jasper. The material is quite attractive when polished and is used as an ornamental stone or gemstone.
401	ORPIMENT	Sulfide mineral	Orange-yellow, lemon-yellow	1½ - 2	3.49	Transparent	Uncommon	Georgia, Hungary, Indonesia, Ireland, Kyrgyzstan	Arsenic sulfide	Orpiment is known as "King's Yellow", "Chinese Yellow" and "Yellow Orpiment". It is often found in association with realgar. It takes its name from the Latin auripigmentum because of its deep yellow color
402	ORTHOCLASE	Igneous	Green, Grey-Yellow, White, Pink, Colorless	6	2.55 - 2.63	Transparent to Opaque	Very Common	Worldwide	Feldspar Orthoclase	Orthoclase is one of the most common minerals, and occurs in numerous mineral environments. It is polymorphous with the minerals Microcline and Sanidine. These three minerals form the Potassium Feldspar group.
403	ORTHOCERAS									Please check fossil.
404	OTHER
405	PALM WOOD JASPER									Please see jasper.
406	PAPAGOITE	Cyclosilicate	Light blue	5-5.5		Transparent to translucent	uncommon	Arizona,Usa	calcium copper aluminium silicate hydroxide	it's bright blue color is the mineral's most notable characteristic.It is used as a gemstone.
407	PARRAL DENDRITIC AGATE									Please see Agate
408	PARSETTENSITE	Manganese	Copper Red	1.5	2.54	Opaque	Uncommon	Italy, New Zealand, Japan, the United States, and South Africa	Modulated Layer Silicate Group	Parsettensite was named for its type locality at Parsettens Alpe in Switzerland. It is an uncommon mineral found in just a few localities including, additionally, Italy, New Zealand, Japan, the United States, and South Africa. Parsettensite can be found in and around manganese deposits.
409	PEARL	Pearl	White-silver, rose, green, blue, black	2½	2.65 - 2.78	Opaque	Common	Persian Gulf, Southeast Asia, India, Sri Lanka, Australia, Central America	Calcium Carbonate	The word "pearl" is synonymous with "bead". Valuable pearls occur in the wild, but they are very rare. Pearls from the sea are valued more highly than freshwater pearls.
410	PEANUT WOOD							Argentina,Australia ,Belgium,Brazil		See petrified wood.
411	PECTOLITE	Pyroxenoid	White, colorless or gray, pale to sky blue	4.5 -5	2.7 -2.9	Transparent to Translucent	Common	USA, Dominican Republic, Italy, England	Sodium Calcium Silicate Hydroxide	Pectolite is a nice specimen type mineral, meaning that it can form interesting specimens from time to time. However it was not all that well-regarded until a variety was discovered in the Bahamas and the Dominican Republic.
412	PERIDOT	Peridot	Yellow-green, olive-green, brown	6½ - 7	3.28 - 3.48	Transparent to Translucent	Common	Burma, Australia, Brazil, China, Kenya, Mexico, Pakistan, Sri Lanka, South Africa, Tanzania	Magnesium Iron Silicate	Peridot is gem-quality olivine (olivine is a silicate mineral). As peridot is the magnesium-rich variety (forsterite) the formula approaches Mg2SiO4. The name derives from Greek, but the meaning is uncertain.
413	PETOSKEY STONE	Rock Fossil	Light green, light grey	4.5 - 5	2.56	Opaque	Common	Michigan	Fossilized Coral	A Petoskey stone is a rock and a fossil, often pebble-shaped, that is composed of a fossilized coral, Hexagonaria percarinata.
414	PETRIFIED PALM	Chalcedony	Varies	7	1.9 - 2.5	Opaque	Common	Hungary, Indonesia, Libya, Thailand, New Zealand	Silicon Dioxide	Petrified wood is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization. All the organic materials have been replaced with minerals , while retaining the original structure of the stem tissue.
415	PETRIFIED WOOD	Chalcedony	Varies	7	1.9 - 2.5	Opaque	Common	Hungary, Indonesia, Libya, Thailand, New Zealand	Silicon Dioxide	Petrified wood is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization.
416	PETROLEUM									A liquid mixture of hydrocarbons that is present in certain rock strata and can be extracted and refined to produce fuels including gasoline, kerosene, and diesel oil.
417	PHENAKITE	Phenakite	Colorless, white, tinted yellow, brown and pink	7.5 - 8	2.9 - 3	Transparent to Translucent	Uncommon	Russia, Brazil, California, USA, Norway	Beryllium silicate	Phenakite is a rare beryllium mineral, but it is found so frequently with precious gemstones that its availablity is not in proportion to its rarity. It is found in pegmatitic pockets and is associated with gemstones such as topaz, beryl especially emerald, chrysoberyl and smoky quartz.
418	PHORPHYRY									Please check Rhyolite.
419	PHOSPHATE									A type of chemcial composition forming a stone
420	PHOSPHOSIDERITE	Metavariscite	Peach-blossom-red, reddish violet, reddish purple, yellow-orange	3½ - 4	2.74 - 2.76	Transparent, Translucent	Common	Germeny		Phosphosiderite is named after its composition: phosphate and iron (Greek - sideros)
421	PHOSPHOPHYLLITE	Phosphate	Blue-green to colorless, gray or black	3 - 3.5	3.1	Transparent to Translucent	Uncommon	Bolivia, USA, Germany	Hydrated Zinc Iron Manganese Phosphate	Phosphophyllite, whose cumbersome name means "phosphate leaf" in allusion to both its chemistry and cleavage, is a rare zinc and manganese mineral that is found at only a few localities.
422	PICASSO MARBLE									Is a form of marble. See Marble.
423	PIETERSITE	Chalcedony	Blue, red, gold, brown	5	2.6	Translucent to Opaque	Common	China and Africa	Magnesium Iron Silicate	Pietersite is the trade name for a (usually) dark blue-gray breccia aggregate made up mainly of hawk's eye and tiger's eye. It was discovered by a man named Sid Pieters in 1962 in Namibia. He registered his find in Britain and the discovery was published in 1964.
424	PIETERSITE GREEN									See Pietersite
425	PILBARA JASPER	Chalcedony	Red, yellow, brown, green, blue	6½ - 7	2.58 - 2.91	Opaque	Common	Egypt, Australia, Brazil, India, Canada, Kazakhstan, Madagascar, Russia	Silicon Dioxide	The appeal of Jasper is its interesting color patterns and formations. Though it can be a solid color, it is most often mottled, spotted, ringed, or striped. Each Jasper has a unique color or pattern, lending this gemstone much variety. Jasper is an opaque form of Chalcedony.
426	PINCTADA MAXIMA	Pearl Oyster	White-silver, rose, green, blue, black	2½	2.65 - 2.78	Opaque	Common	Australia, Fiji, Tahiti, Indonesia, Philippines	Calcium Carbonate	Pinctada Maxima pearl oyster produces some the finest and most beautiful pearls in the world. The size of the shell is huge in comparison to any other shell available and caused a sensation in European and American markets when it first appeared. The average size of the shell is six to twelve inches.
427	PINOLITH		Black to grey	3.5-4				Styria, Austria		Pinolith is named for the appearance of the magnesite kernels found within the material. With their shape and color, it was first compared to pine nuts in early found rock.
428	PINK OPAL									Please see Opal
429	PINK LIMCAST
430	PIPE STONE	Clay	Light brown, light red	1 - 2	2.08	Opaque	Common	Pipestone Minnesota and Pipestone River Ontario	Potassium aluminum silicate Hydroxyide fluoride	Pipestone is a type of argillite (metamorphosed mudstone), usually brownish-red in color. Because it is fine-grained and easily worked, it is prized by Native Americans for use in making sacred pipes.
431	PAINITE	Hexagonal	Red, brownish, orange-red	8	4 - 4.03	Transparent	uncommon	Mayanmar
432	PIRATES									Pirates is one of the only gemstones that comes in only one color. Depending on iron count in gem, gems can appear pale yellow/green all the way to a rich deep olive color. Origin of name “Peridot” is unclear. It's only gemstone found in meteorites.
433	PIRITA			6 – 6.5						please check pyritesi
434	PLANCHEITE	Chain Silicate	Blue, blue-green	6	3.65 - 3.8	Translucent	Uncommon	France, Italy, Japan, Mexico, Namibia, Norway, South Africa, UK	Hydrated Copper Silicate Hydroxyide	Plancheite is another in the long list of secondary copper minerals. And like so many of them, this one is colorful, attractive, has interesting crystal habits and is definitely a good collection mineral. Its almost turquoise-like color is unique and its typical fibrous.
435	PLATINUM	Metal	Steel to dark grey	4 - 4½	14 - 19	Opaque	Uncommon	Colombia, Japan, Papua New Guinea, Philippines, Russia	Platinum	Platinum is a chemical element. A dense, malleable, ductile, precious, gray-white transition metal, platinum is resistant to corrosion and occurs in some nickel and copper ores along with some native deposits.
436	PLUME STONE	Agate	Dark to light green	5.5-6	2.58 - 2.64	Opaque	Common	USA, Canada	Varies	In allusion to the plume-like shapes exhibited in the material.
437	POLONIUM									Polonium is a chemical element with the symbol Po and atomic number 84. A rare and highly radioactive element with no stable isotopes, polonium is chemically similar to bismuth and tellurium, and it occurs in uranium ores.
438	POLYCHROME JASPER	Chalcedony	Mixed	6½ - 7	2.58 - 2.91	Opaque	Uncommon	Madagascar	Iron Oxide	Polychrome Jasper is a beautifully vivid multicolored specimen.While searching for the now mined-out mineral, Ocean Jasper, a discovery of Polychrome Jasper was made in Madagascar.
439	POLYGRAM JASPER									Please see Jasper
440	PORCELAIN JASPER									Please see Jasper
441	PORPHYRY	Igneous	Brown, purple	3	2.54	Opaque	Uncommon	Egypt	Sodium Carbonate	Porphyry is a variety of igneous rock consisting of large-grained crystals, such as feldspar or quartz, dispersed in a fine-grained feldspathic matrix or groundmass.
442	POWELLITE	Molybdate	Yellow, Grey, Brown, Blue and Black	3 - 4	4.25	Transparent to Translucent	Common	USA, India, Turkey, Russia, Scotland	Calcium Molybdate	Powellite is named for the American geologist, Major John Wesley Powell, a former director of the U. S. Geological Survey. Most of powellite's occurrences are the result of hydrothermal reactions with the primary sulfide mineral molybdenite.
443	PRASIOLITE	Quartz	Light green, colorless	7	2.65	Transparent to Opaque	Uncommon	Brazil, Madagascar and Myanmar	Silicon Dioxide	Prasiolite is the green variety of Quartz. The material is extremely rare in nature and is only found in a handful deposits.
444	PRECIOUS STONE									A precious or semi-precious stone is a piece of attractive mineral, which—when cut and polished—is used to make jewelry or other adornments. Diamond, Emerald, Ruby, Sapphire and Pearls etc
445	PREHNITE	Prehnite	Yellow-green, brown-yellow	6 - 6½	2.82 - 2.94	Transparent to Translucent	Common	Australia, China, Scotland, South Africa and United States	Beryllium Silicate	It comes under Silicates group. Rare tabular , light green crystals. More often in greenish-white reniform, stalactitic or mammillary.
446	PRINTADA MAXIMA
447	PRINT STONE	Limestone	White, yellow, light brown, pink, red	3 - 4	2.50 - 2.70	Opaque	Common	Biochemical Origin	Calcium Carbonate	Lithographic limestone is hard limestone that is sufficiently fine-grained, homogeneous and defect free to be used for lithography. Geologists use the term lithographic texture to refer to a grain size under 1/250 mm. The term sublithographic is sometimes used for homogeneous fine-grained limestone with a somewhat coarser texture.
448	PROMECERAS
449	PROUSTITE	Proustite	Dark red, red-grey, vermilion	2 - 2½	5.57	Translucent to Opaque	Uncommon	Fiji, France, Hungary, Indonesia, Ireland, Italy, Madagascar	Silver Arsenic Sulfide	Proustite is a sulfosalt mineral consisting of silver sulfarsenide, known also as light red silver or ruby silver ore, and an important source of the metal. It is closely allied to the corresponding sulfantimonide, pyrargyrite.
450	PSILOMELANE		Iron-black	5.0 - 6.0	4.7 - 4.72	Opaque	Common			Psilomelane are the barium manganese hydroxides that do not create visible crystals. They are originally considered a mineral species until they were discredited in 1982 by the International Mineralogical Association.
451	PUDDING STONE	Conglomerate	Grey-brown, stone grey	2.5-3	2.5 - 2.8	Opaque	Uncommon	Hertfordshire, Schunemunk, Roxbury, and St. Joseph Island	Varies	Puddingstone is a popular name applied to a conglomerate that consists of distinctly rounded pebbles whose colors contrast sharply with the color of the finer-grained, often sandy, matrix or cement surrounding them.
452	PURPURITE	Triphylite	Brownish black, violet, dark pink, dark red, reddish purple	4 - 4½	3.2 - 3.4	Opaque	Common	USA,Australia, Namibia, France	Manganese phosphate,	Purpurite's color is purple, and although it is usually quite a deep purple, some pieces may be pinkish or lavender purple.
453	PYRARGYRITE	Proustite	Deep red, red-grey	2½	5.82	Opaque	Uncommon	Bolivia, Bulgaria, Ecuador, Eritrea, Fiji, Hungary	Silver Antimony Sulfide	Pyrargyrite is a popular silver bearing mineral for collectors.The nickname "Ruby Silver" has been applied to pyrargyrite although it is typically applied to the related mineral proustite. Pyrargyrite is isostructural with proustite, a silver arsenic sulfide.
454	PYRITE	Pyrite	Brass-yellow, grey-yellow	6 - 6½	5.00 - 5.20	Opaque	Very Common	Peru, Bolivia, Mexico, Romania, Sweden, United States	Iron Sulfide	Pyrite is wrongly called marcasite in the trade. True marcasite is a mineral, in many ways similar to pyrite. Because of its similarity to gold also called Fool's Gold.
455	PYRITE CUBE									Please see pyrite.
456	PYRITE WITH QUARTZ									Please see Pyrite and Quartz
457	PYROLUSITE	Rutile	Black, dark grey, shades of blue	6 - 6½	4.4 - 5.06	Opaque	Uncommon	USA, Mexico, Namibia, Iran, Spain, China, Japan	Manganese Oxide	Pyrolusite is a mineral consisting essentially of manganese dioxide(MnO2) and is important as an oreof manganese. It is a black, amorphous appearing mineral, often with a granular, fibrous or columnar structure, sometimes forming reniform crusts.
458	PYROMORPHITE	Apatite	Green to dark green, yellow, orange-yellow, white, colorless	3½ - 4	7.04	Opaque	Common	Germany, Hungary, Ireland, Isle of Man, Italy, Japan, Madagascar, Kazakhstan, Namibia, Morocco	Lead Chlorophosphate	Pyromorphite is a member of the Apatite group, a group of isomorphous hexagonal minerals. It is very similar in structure and appearance to Mimetite, and may be partially replaced by it. It is a typical secondary mineral found in the oxidation zone of lead deposits.
459	PYROX MANCIT	Pyroxene	Light pink, purple	5½ - 6	3.61 - 3.8	Opaque	Common	Worldwide	Manganese Iron Magnesium Calcium Silicate	Easily confused with rhodonite; however, Pyroxmangite is a high-temperature environment mineral and syntheses have shown that pyroxmangite of MnSiO3 composition is the high-pressure, low-temperature polymorph with respect to rhodonite of the same composition.
460	PYROXENE	Pyroxene	Light pink, purple, black	6.5 - 7.0	3.0-4.0	Opaque	Uncommon	Iceland, India, Indonesia, Mars, Kazakhstan, Libya,	Clinopyroxene	The pyroxenes are closely related to a group of inosilicates called the pyroxenoids. This somewhat informal group of minerals has a similar chain structure but the chains in the pyroxenoid structures are more "kinked".
461	PYROXMANGITE	Pyroxene	Light pink, purple	5½ - 6	3.61 - 3.8	Opaque	Common	Worldwide	Manganese Iron Magnesium Calcium Silicate	Easily confused with rhodonite; however, Pyroxmangite is a high-temperature environment mineral and syntheses have shown that pyroxmangite of MnSiO3 composition is the high-pressure, low-temperature polymorph with respect to rhodonite of the same composition.
462	PYRRHOTITE	Pyrrhotite	Bronze brown, bronze red, dark brown	3½ - 4	4.58 - 4.65	Opaque	Common	Armenia, Cuba, Ghana, India, Iran	Iron Sulfide	Pyrrhotite has some unusual characteristics. First, it has an unusual formula. Secondly, it has two symmetries. While this should indicate that there are two minerals and not one, in the case of pyrrhotite, mineralogists have made an exception.
463	QUARTZ	Quartz	White, grey, green, yellow, brown	6½ - 7	2.58 - 2.64	Transparent to Translucent	Very Common	Germany, Hungary, Ireland, Isle Of Man, Italy, Japan, Madagascar, Kazakhstan, Namibia, Morocco	Silicon Oxide	Quartz belongs to the rhombohedral crystal system. The ideal crystal shape is a six-sided prism terminating with six-sided pyramids at each end. In nature quartz crystals are often twinned, distorted, or so intergrown with adjacent crystals of quartz or other minerals.
464	QUARTZ W/ IRON									Please see Quartz and Iron
465	RADIUM	Radioactive Element	Colorless to Black	N/A	5.5	Transparent to Opaque	Uncommon	N/A	Uranium Oxide	Radium is a radioactive chemical element. Its appearance is almost pure white, but it readily oxidizes on exposure to air, turning black. Radium is an alkaline earth metal that is found in trace amounts in uranium ores. It is extremely radioactive.
466	RAINBOW CALSILICA									See Silica
467	RAINBOW GARNET									See Garnet.
468	RAINBOW OBSIDIAN									See Obsidian
469	RED JASPER	Chalcedony	Red, yellow, brown, green, blue	6½ - 7	2.58 - 2.91	Opaque	Common	Egypt, Australia, Brazil, India, Canada, Kazakhstan, Madagascar, Russia	Silicon Dioxide	The appeal of Jasper is its interesting color patterns and formations. Though it can be a solid color, it is most often mottled, spotted, ringed, or striped. Each Jasper has a unique color or pattern, lending this gemstone much variety. Jasper is an opaque form of Chalcedony.
470	RED MARBLE	Calcite	White, green, grey-brown, blue-grey	3	2.76	Opaque	Very Common	Afghanistan, Argentina, Austria, Canada, Norway, USA	Calcium Carbonate	Marble is the product of metamorphism on Limestone. Typically this metamorphic rock is composed primarily of carbonates, primarily Calcite (Calcium Carbonate).
471	REALGAR		Orange to red	1.5 - 2	3.5 - 3.6	Transparent to Translucent	Common	China, Switzerland, Japan, USA	Arsenic Sulfide	Realgar is an oddball among the sulfides. It is one of only a few sulfides that are not metallic or opaque or blandly colored. Its structure is analogous to that of sulfur and resembles sulfur in most respects except for color (the name "ruby sulfur" has been applied to realgar).
472	REMONDITE	Carbonate	White, pink, orange and yellow	3 - 3.5	3.43	Transparent to Translucent	Uncommon	Cameroon, Canada, Russia	Sodium Calcium Strontium Barium Cerium Carbonate	Remondite is named in honor of Dr. Guy Rémond, a physicist for the Bureau de Recherches Géologiques et Minières in Orléans, France who worked extensively on the physics of minerals.
473	RHODOCHROSITE	Rhodochrosite	Rose-red, yellow, striped	4	3.45 - 3.70	Translucent to Opaque	Common	Chile, Mexico, Peru, South Africa and United States	Manganese Carbonate	Rhodochrosite has been on the market only since about 1950. Transparent crystals are very rare. The aggregates are light-dark strips with zigzag bands. Usually used in larger pieces.
474	RHODOLITE	Garnet Intermediate Varities	Red, brown-red, violet, black	6½ - 7½	4,2	Transparent to Translucent	Common	Greenland, Kenya, Mozambique, Norway, Sri Lanka, USA	Magnesium Aluminum Silicate	Rhodolite is a varietal name for rose-pink to red mineral pyrope, a species in the garnet group.
475	RHODONITE	Rhodonite	Dark red, flesh red, black	5½ - 6½	3.40 - 3.74	Translucent to Opaque	Uncommon	Australia, Finland, Japan, Canada, Madagascar, Mexico, Russia, Sweden, South Africa, Tanzania and United States	Manganese Silicate	Rhodonite in addition to its red color usually has black dendritic inclusions of manganese oxide. Transparent varieties are very rare and faceted with table or brilliant cut.
476	RHYOLITE	Chalcedony	Light Brown, pink	6.5 to 7	2.4 – 2.6	Opaque	Common	Madagascar, Russia, USA	Beryllium Aluminum Silicate	Rhyolite is extrusive igneous rock that is the volcanic equivalent of granite. Most rhyolites are porphyritic, indicating that crystallization began prior to extrusion.
477	RICOLITE	Serpentine	Light green, light brown	4 - 5	2.5	Translucent to Opaque	Common	USA & New Mexico	Magnesium Iron Silicate Hydroxyide	A variety of serpentine interbanded with talc.
478	ROCKS / STONES									Rocks are classified by mineral and chemical composition, by the texture of the constituent particles and by the processes that formed them.
479	ROSE QUARTZ	Quartz	Dark to light pink	7	2.65	Transparent to Translucent	Very Common	Brazil, Madagascar, India, Mozambique, Namibia, Sri Lank and United States.	Silicon Dioxide	Rose quartz is a translucent, usually turbid, very coarse-grained variety of the silica mineral quartz found in pegmatites.
480	ROSELITE	Arsenate	Dark rose red, pink	3.5	3.69	Translucent to Opaque	Rare	Germany, Italy, Morocco	Hydrated Calcium Cobalt Magnesium Aresenate	Roselite is a rare arsenate mineral. It was first described in 1825 for an occurrence in the Rappold mines of Schneeberg, Saxony, Germany and named for German mineralogist Gustav Rose who discovered this mineral.
481	RUBELLITE	Tourmaline	Pink, red, black, violet, green	7	2.98 - 3.2	Transparent to Translucent	Common	Nepal, South Korea, Spain, Sweden, Tajikistan, UK, USA, Zimbabwe	Sodium Lithium Aluminum Boro-Silicate Hydroxyide	The Rubellite is a particularly beautiful gemstone from the colorful family of the tourmalines. Its color shines in the most beautiful nuances from red to shocking pink.
482	RUBIN CRYSTAL									Please see Crystal
483	RUBY	Corundum	Varying red	9	3.97 - 4.05	Translucent	Common	Cambodia, Kenya, Nepal, New Zealand, Norway, Pakistan, Somaliland, Sri Lanka	Aluminum Oxide	Ruby is named because of its color. The hardest mineral after diamond, although only 1/40 as hard, it is seven times as hard as topaz. It has no cleavage, but has certain preferred directions of parting.
484	RE-CRYSTALLIZED RUBY									Please see Ruby
485	RUBY ROCK									Please see Ruby
486	RUBY IN ZOISITE	Corundum	Varying red	9	3.97 - 4.05	Translucent	Common	Cambodia, Kenya, Nepal, New Zealand, Norway, Pakistan, Somaliland, Sri Lanka	Aluminum Oxide	Ruby is named because of its color. The hardest mineral after diamond, although only 1/40 as hard, it is seven times as hard as topaz. It has no cleavage, but has certain preferred directions of parting. Because of brittleness, care must be take when cutting and setting.
487	RUBY W/ SAPPHIRE									Please see Ruby and Sapphire
488	RUTILE QUARTZ	Rutile	Red-brown, blood-red or black	6 - 6½	4.20 - 4.30	Transparent to Opaque	Uncommon	Burundi, Burma, Chad, Chile, Cuba, Egypt, Ethiopia, Fiji, Finland, Serbia	Titanium Oxide	Rutilated quartz is a rare mineral that is mainly made up of titanium dioxide.
489	SALOME MARBLE									Please see Marble
490	SALT	Sodium	Light grey, white	2	2.16	Transparent to Translucent	Common	Worldwide	Sodium Chloride	Salt is a dietary mineral composed primarily of sodium chloride that is essential for animal life, but toxic to most land plants. Salt flavor is one of the basic tastes, an important preservative and a popular food seasoning. Salt for human consumption is produced in different forms.
491	SALT PETER	Potassium	Colorless or white, light yellow, grey	2	2.11	Transparent to Translucent	Common	Australia, Bahamas, Bolivia, Bulgaria, Germany, Chile, South Africa	Potassium Nitrate	Known as Saltpeter or Niter. Because of its ready solubility in water, niter is most often found in arid environments. A major source of sodium nitrate mineral ("Chile saltpeter", that is, nitratine) is the Atacama desert in Chile.
492	SMITHSONITE	Calcite	Grayish white, Dark gray, Green, Blue, Yellow	4.5	4.4 - 4.5	Translucent to nearly opaque	Uncommon	washington,USA	Zinc carbonate	Smithsonite rarely occurs in visible crystals. The only two locations to produce large crystals of significance are Tsumeb, Namibia; and Broken Hill, Zambia. Virtually all other findings of this mineral are in globular or botryoidal-like forms.
493	SANDSTONE	Quartz	Tan, brown, yellow, red, grey, pink, white	6.5 - 7	2.2 - 2.8	Opaque	Common	Burundi, Burma, Chad, Chile, Cuba, Egypt, Ethiopia, Fiji, Finland, Serbia	Sedimentary Rock	Sandstone is a sedimentary rock composed mainly of sand-size mineral or rock grains. Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust.
494	SAPPHIRE	Corundum	Blue, colorless, pink, orange, yellow, green, purple, black	9	3.95 - 4.03	Transparent to Opaque	Common	Laos, Nepal, New Zealand, Pakistan, Malawi, India, Vietnam, Zimbabwe	Aluminum Oxide	In antiquity and as late as the Middle Ages, the name sapphire was understood to mean what is today described as lapis lazuli. Today corundums of gemstone quality of all colors except red are called sapphire.
495	SCAPOLITE	Tectosilicates	White, grey, light brown, pink, yellow	6	2.56 - 2.77	Translucent to Opaque	Very Common	Canada, Burma, Madagascar	Sodium Aluminum Silicate with Chlorine	Scapolite, which is the Greek word for shaft, is commonly found in stubby to long prismatic crystals. It is an aluminum silicate mineral with sodium and calcium and is part of a series whose end members are marialite and meionite.
496	SCHALEN BLENDE		Beige to brown			Opaque
497	SCHEELITE	Scheelite	Tan, golden-yellow, colorless, white, green, dark brown, colorless	4½ - 5	6.1	Transparent to Translucent	Uncommon	Uzbekistan, Sweden, Venezuela, Zimbabwe, Sweden	Calcium Tungstate	Scheelite is an important ore of tungsten which is a strategically important metal. Scheelite is a popular mineral for collectors. It forms perfect tetragonal dipyramidal crystals that look very much like octahedrons.
498	SCHIST	Metamorphic Rock	Green, grey, dark brown, silver	6 - 7	2.5 - 2.9	Opaque	Common	Varies	Metamorphic Rock	Schist is a crystalline metamorphic rock, mostly composed of more than 50% tabular and elongated minerals with grainsize coarse enough to be visible to the unaided eye. Schists have a developed tendency to split into layers.
499	SCIENTIST									A scientist, in the broadest sense, refers to any person that engages in a systematic activity to acquire knowledge or an individual that engages in such practices and traditions that are linked to schools of thought or philosophy.
500	SCOLECITE	Natrolite	Colorless, white, pink, salmon, red, green	5 - 5½	2.25 - 2.29	Opaque	Common	Russia, Slovakia, South Africa, Spain, Switzerland, Taiwan, Tanzania	Hydrated calcium aluminum silicate	Scolecite is a tectosilicate mineral belonging to the zeolite group; a hydrated calcium silicate. Its name came from the Greek word 'worm' because of its reaction to the blowpipe flame.
501	SHARK TEETH									Please check fossil.
502	SELENITE	Gypsum	Brown-green, brown-yellow, grey-green	2	2.36	Transparent to Translucent	Common	Naica, Mexico; Sicily; Utah and Colorado, USA	Hydrated Calcium Sulfate	Selenite is a variety of the mineral gypsum and shows obvious crystalline structure. The four "crystalline" varieties of gypsum are sometimes grouped together and called selenite.
503	SEPIOLITE	Sepiolite	White, light grey, light yellow	2 - 2.5	2.0 - 2.1	Opaque	Common	China, Greece, Hungary, Kenya, Malaysia, Norway, Turkey	Potassium aluminum silicate Hydroxyide fluoride	Sepiolite is a clay mineral, a complex magnesium silicate. It is used in oil drilling, for cat litter. Owing to its fibrous mineral nature, sepiolite veins may contain the hazardous material, asbestos; even where asbestos is not present, sepiolite is often mistaken for it.
504	SEPTA CALCITE									Please see Septaria and Calcite
505	SEPTERIA	Sedimentary	Bright red, golden, grey	2 - 3	2.6	Opaque	Common	Mexico, USA, Madagascar	Calcium Carbonate	Septarian concretions or septarian nodules are concretions containing angular cavities or cracks, which are called "Septaria". The word comes from the Latin word septum; "partition", and refers to the cracks/separations in this kind of rock.
506	SEPTERIA JASPER	Chalcedony	Red, yellow, brown, green, blue	6½ - 7	2.58 - 2.91	Opaque	Common	Egypt, Australia, Brazil, India, Canada, Kazakhstan, Madagascar, Russia	Silicon Dioxide	The appeal of Jasper is its interesting color patterns and formations. Though it can be a solid color, it is most often mottled, spotted, ringed, or striped. Each Jasper has a unique color or pattern, lending this gemstone much variety.
507	SERAPHINITE	Clinochlore	Dark Green, Grey	2 - 2.5	2.6	Opaque	Uncommon	Siberia, Russia	Magnesium Iron Aluminum Silicate Hydroxyide	Seraphinite is a dense fine-grained variety of clinochlore which is used for carving and as a decorative stone.
508	SERENDIBITE		pale yellow, blue-green, greyish blue, black	6.5-7	3.42 - 3.52	Transparent				serendibite mineral is found in skarns associated with boron metasomatism of carbonate rocks where intruded by granite.
509	SERPENTINE	Serpentine	Green, yellow	2½ - 5½	2.44 - 2.62	Opaque	Very Common	Afghanistan, China, New Zealand and United States	Hydroxyy Silicate of Magnesium	There are two aggregate structures for serpentine: leafy serpentine and fibrous chrysotile. Very finely fibrous varieties are called asbestos.
510	SERPENTINE W/ MICA									Please see Serpentine and Mica
511	SHELL	Organic Shell	White, light yellow, varies	3 - 4	2.3	Opaque	Very Common	Worldwide	Calcium Carbonate	The term seashell usually refers to the exoskeleton of an invertebrate (an animal without a backbone). Most shells that are found on beaches are the shells of marine mollusks, partly because many of these shells endure better than other seashells.
512	SHORTITE	Trona	Colourless, light yellow, light green	3	2.6	Transparent to Translucent	Uncommon	USA, Russia, Canada	Sodium calcium carbonate	Shortite is a sodium calcium carbonate mineral. It was discovered by J. J. Fahey in well cuttings from the Green River Formation, Sweetwater County,
513	SHATTUCKITE	Silicates	Bright blue, turquoise blue, dark blue	3.5	4.1	Translucent	Uncommon	Nambia, Congo, USA	Basic copper silicate	Shattuckite is an uncommon copper mineral that is highly regarded for its vivid blue color. It is named after the Shattuck Mine in Bisbee, Arizona, where this mineral was first discovered. Shattuckite occasionally forms within Quartz crystals, underneath the top layer.
514	SHUNGITE		Black					Russia, India		Shungite has been used since the middle of the 18th century as a pigment for paint and is currently sold under the names "carbon black" or "shungite natural black
515	SIDERITE	Siderite	Yellow-brown, grey-brown, pale yellow, tan	3.75 - 4.25	3.96	Translucent to Opaque	Common	Pribram, Bohemia, Czech Republic	Iron Carbonate	Siderite is typically found as brown to tan rhombohedrons in clusters, faces often curved or composites; more often found as medium to dark brown massive fine grained material or as massive crystalline material with exposed curved cleavage surfaces.
516	SILICA	Natural Glass	Grey	7	2.648	Transparent	Very Common	Bolivia, Chile, India, Japan, Pacific Ocean, UK, USA	Silicon	Silica is a form of silicon, one of the most common elements on earth. Earth’s crust, silicon is the second most abundant element after oxygen, making up 27.7% of the crust by mass. Found in rocks and stones.
517	SILICIFIED WOOD	Petrified Wood	Varies	7	1.9 - 2.5	Opaque	Common	Hungary, Indonesia, Libya, Thailand, New Zealand	Iron Oxide	A variety of Chalcedony. Fossil wood replaced by chalcedony (cryptocrystalline quartz), sometimes also by opal, coal, pyrite, calcite.
518	SILICON								Elemental Silicon	Silicon is a chemical element with the symbol Si and atomic number 14. Silicon is rarely found in nature in its uncombined form. In fact it is amazing how rare native silicon is with 25.7% of the Earth's crust being silicon.
519	SILLIMANITE	Sillimanite	Light and dark green, blue	6½ - 7½	3.24	Transparent to Translucent	Common	Algeria, China, India, Madagascar, Peru, Poland, Portugal, Russia, Slovakia	Aluminum Silicate	An industrial mineral used in the manufacture of re-fractories and high-temperature crucibles. It is a sensitive indicator of the temperature and pressure at which the host rock formed.and pressure at which the host
520	SILVER	Metal	Silver-white, dark grey, black	2½ - 3	10.1 - 11.1	Opaque	Uncommon	Belgium, Bolivia, China, Cube, Georgia	Silver	Silver has been known since ancient times and has long been valued as a precious metal, used to make ornaments, jewelry, high-value tableware, utensils (hence the term silverware), and currency coins.
521	SILVER EYE									Please see silver.
522	SKUTTERUDITE	Cobalt Arsenide	Silver white to gray	5.5 - 6	6.4 - 6.9	Opaque	Uncommon	Spain, Canada, Germany	Cobalt nickel arsenide	The Skutterudite series is a group of closely related arsenide minerals with varying rates of cobalt, nickel, and sometimes iron. The cobalt-rich end member is Skutterudite, and the nickel-rich end member is Nickelskutterudite. .
523	SMARAGDITE	Amphibole	Green	5.5	3.24 - 3.50	Translucent to Opaque	Uncommon	Austria, France, Italy, USA	Calcium, Magnesium, Iron Silicate	A fibrous green amphibole mineral occurring in rocks such as eclogite. The color is due to small amounts of chromium. Mineralogically it is not related to emerald. An emerald imitation from fused masses is also called Smaragdite.
524	SMOKY QUARTZ	Quartz	Brown, black, smoky grey	7	2.65	Transparent	Common	Brazil, Madagascar, Russia, Scotland, Switzerland and Ukraine.	Silicon Dioxide	Named after its smoky color. Very dark stones are called "morion" and " cairngorm". Smoky yellow quartz also occurs. The name smoky topaz is improper and no longer acceptable in the trade.
525	SMOKY QUARTZ W/ AMAZONITE	Quartz	Brown, black, smoky grey	7	2.65	Transparent	Common	Brazil, Madagascar, Russia, Scotland, Switzerland and Ukraine.	Silicon Dioxide	Named after its smoky color. Very dark stones are called "morion" and " cairngorm". Smoky yellow quartz also occurs. The name smoky topaz is improper and no longer acceptable in the trade.
526	SOAPSTONE	Smectite	Green, brown, grey	1 - 1½	2.2-2.8	Translucent to Opaque	Very Common	Australia, Chile, Norway, USA	Magnesium Silicate Hydroxyide	Soapstone (also called steatite) is a soft, easily-carved, fine-grained metamorphic rock that can be green, brown, or gray. This stone has a greasy, soapy feel to it, hence its name. Soapstone is found worldwide.
527	SODALITE	Sodalite	White, blue, grey	5 1/2 - 6	2.14 - 2.40	Opaque	Common	Brazil, Greenland, India, Canada, Namibia, Russia and United States	Sodium Aluminum silicate with sodium chloride	The name sodalite refers to its sodium content. For jewelry, only blue tones are used sometimes they have a violet tint; frequently they are dispersed with white veins from white calcite.
528	SOIL									The upper layer of earth in which plants grow, a black or dark brown material typically consisting of a mixture of organic remains, clay, and rock particles.
529	SOLAR GREEN									Please check greenstone.
530	SONORA AGATE	Chalcedony	White, grey, green, yellow, brown	6½ - 7	2.58 - 2.64	Opaque	Very Common	Angola, Armenia, Bulgaria, India, Jamaica, Panama, Papua New Guinea	Silicon Dioxide	Agate is a microcrystalline variety of quartz, chiefly chalcedony, characterized by its fineness of grain and brightness of color. Although agates may be found in various kinds of rock.
531	SONORA JASPER									See Jasper
532	SOUZALITE	Triclinic	Blue-green, dark grey-green	5.5 - 6	3.087	Translucent to Opaque	Uncommon	Córrego Frio mine, Linópolis, Divino das Laranjeiras, Doce valley, Minas Gerais, Brazil	Hydrated Iron Magnesium Aluminum Phosphate Hydroxyide	Souzalite is a triclinic mineral containing aluminum, hydrogen, iron, magnesium, oxygen, and phosphorus
533	rphy	Feldspar Plagioclase	Full spectrum of colors, violet, blue, green, yellow, orange, red	6 - 6.5	2.69 - 2.72	Opaque	Uncommon	Finland	Sodium calcium aluminum silicates	Spectrolite is the name given to rare specimens of labradorite, which display a full spectrum of colors, not only violet, blue and green; but also yellow, orange and red.
534	SPECTITE
535	SPECULAR HEMATITE									Please see Hematite
536	SPESSARTINE (SPESSARTITE)	Garnet	Orange, red-brown	6½ - 7½	4.12 - 4.18	Transparent to Translucent	Uncommon	Burma, Brazil, China, Kenya, Madagascar, Sri Lanka, Tanzania and United Stated	Manganese Aluminum Silicate	The name is a derivative of Spessart in Bavaria, Germany, the type locality of the mineral. It occurs most often in granite pegmatite and allied rock types and in certain low grade metamorphic phyllites.
537	SPHALERITE	Pyrosmalite	Colorless, dark brown, grey, black	3.5-4	3.9 - 4.1	Translucent to Opaque	Common	USA, South America, South Africa, Italy, Indonesia, Thailand, Kazakhstan	Zinc sulfide	Sphalerite (which is also known as Blende), is an important ore of zinc and can make a rather attractive cabinet specimen as well. It can have excellent luster and associates with many beautifully colored minerals.
538	SPHENE	Sphene	Yellow, brown, green, red	5 - 5½	3.52 - 3.54	Transparent to Opaque	Uncommon	Burma, Brazil, Mexico, Austria, Sri Lanka and United States	Calcium Titanium Silicate	Sphene is a rare collector stone. Because of it's high dispersion and refractive index, a well cut sphene can display stunning brilliance.
539	SPINEL	Spinel	Red, yellow, brown	8	3.54 - 3.63	Transparent to Opaque	Common	Azerbaijan, Botswana, Burma, Fiji, Finland, France, Egypt, Germany, French Guiana, Greenland, Greece, Hungary	Magnesium Illuminate	Spinel is a mineral composed of magnesium aluminum oxide or any member of a group of rock-forming minerals. Several varieties of spinel are known like "Ruby spinel" is a semi-precious gemstone.
540	SPIRIT STONE (YAVAPAI TRAVERTINE)									A varient of Travertine. Please see Travertine.
541	SPLASH COPPER	Copper	Metallic golden, brass yellow	3.2 - 3.5	8.9	Opaque	Common	Costa Rica, Cuba, Denmark, Eritrea, Germany, Guatemala, Israel, Jamaica, Laos, Mongolia	Copper	It is a varient of the metal copper.
542	SPODUMENE	Spodumene	Colorless, yellow, light green, emerald-green, pink-violet, white, grey	6½ - 7	3.1 - 3.2	Translucent to Opaque	Common	South Africa, Spain, Sweden, UK, USA, Zimbabwe	Lithium Aluminum Silicate	Spodumene is a pyroxene mineral consisting of lithium Aluminum inosilicate, LiAl(SiO3)2, and is a source of lithium. It occurs as colorless to yellowish, purplish, or lilac kunzite (see below), yellowish-green or emerald-green hiddenite, prismatic crystals, often of great size. It is an important industrial source if lithium and its salts.
543	SPONGE CORAL									Please see coral.
544	STALACTITE (MALACHITE)									Please see Malachite
545	STARBUST JASPER									Please see Jasper
546	STEEL									Steel is the most widely recycled material in the United States.The steel industry has been actively recycling for more than 150 years, in large part because it is economically advantageous to do so.
547	STELLERITE	Zeolite	White. Yellow, Pink	3.5 - 4	2.2	Transparent to Translucent	Uncommon	India, USA, Nova Scotia	Calcium Aluminosilicate Hydrate	Stellerite is the rarer cousin of the much more common zeolite, stilbite. Like stilbite, stellerite crystals can aggregate together to form a structure resembling wheat sheafs.
548	STIBICONITE	Sedimentary	Yellow, yellow-gray, gray, brownish-yellow, brown	4 - 5.5	3.5 - 5	Translucent to Opaque	Uncommon	China, Mexico	Basic antimony oxide	Stibiconite is an alteration mineral of Stibnite. It forms as a dull, crusty yellow replacement mineral over Stibnite. The pseudomorph is occasionally only partial, in which only a section of the crystal has been altered with the rest remaining intact.
549	STIBNITE	Stibnite	Lead-grey with pale blue tint	2	4.63	Opaque	Uncommon	Costa Rica, Cuba, Czech Republic, Ghana, Greece, Guatemala, Hungary	Antimony Sulfide	Stibnite has no significant uses, except as a precursor to antimony oxide, which is the most commonly marketed form of antimony. In ancient times, it was used as mascara called kohl.
550	STICHTITE	Hydrotalcite	Pink, Purple	1.5-2	2.16	Opaque	Uncommon	Australia & Tasmania	Hydrated Magnesium Chromium Carbonate Hydroxyide	Stichtite is a mineral, a carbonate of chromium and magnesium. Its color ranges from pink through lilac to a rich purple color. It is formed as an alteration product from chromium containing serpentine.
551	STILBITE	Zeolite	White, beige, peach, pink, orange, light yellow, brown	3½ - 4	2.18 - 2.2	Translucent to Opaque	Common	Bosnia & Herzegovina, Brazil, Bulgaria	Hydrated Sodium Calcium Aluminum Silicate	Stilbite is a mineral of secondary origin, and occurs with other zeolites in the amygdaloidal cavities of basaltic volcanic rocks; it is sometimes found in granite and gneiss, and exceptionally in hydrothermal veins.
552	STROMATOLITE	Limestone	Grey, white, dark brown	6 - 7	2.3-2.7	Opaque	Common	USA	Calcium Carbonate	Stromatolites or stromatoliths are layered accretionary structures formed in shallow water by the trapping, binding and cementation of sedimentary grains by biofilms of microorganisms.
553	STRONTIANITE	Aragonite	White, grey, light yellow, green, brown, colorless	3½	3.74 - 3.78	Translucent to Opaque	Uncommon	Angola, India, Kazakhstan, Kyrgyzstan, Malawi, Morocco	Strontium Titanate	Strontianite is an important raw material for the extraction of strontium. It is a rare carbonate mineral and one of only a few strontium minerals. It is a member of the aragonite groupIt is an important raw material for the extraction of strontium
554	STRUVITE	Struvite	Colorless, white, yellow, brown, light grey	1½ - 2	1.711	Opaque	Uncommon	Kosovo, Malaysia, Namibia, Netherlands, South Africa, USA	Hydrated Ammonium Magnesium Phosphate	Struvite (ammonium magnesium phosphate) is a phosphate mineral. Struvite crystallizes in the orthorhombic system as white to yellowish or brownish-white pyramidal crystals or in platey mica-like forms.
555	STYLOLITE									Stylolite is sedimentary structure consisting of a series of relatively small, alternating, interlocked, toothlike columns of stone; it is common in limestone, marble, and similar rock.
556	SUGILITE		Light brownish-yellow, purple, violet, reddish violet, pale pink, colorless	6–?6.5		Translucent	Common	Italy, Australia and India	Cyclosilicate	Sugilite was first described in 1944 by the Japanese petrologist Ken-ichi Sugi (1901–1948) for an occurrence on Iwagi Islet, Japan, where it is found in an aegirine syenite intrusive stock.
557	SULPHUR	Sulphur	Yellow, sulphur-yellow, green-yellow, orange, white	1½ - 2½	2.07	Transparent to Translucent	Uncommon	Afghanistan, Algeria, Croatia, Gulf of Mexico, Hungary	Sulfur	Sulfur or sulphur is the chemical element. It is an abundant multivalent non-metal. Sulfur, in its native form, is a yellow crystalline solid.
558	SUNSTONE (ORI SUNSTONE)	Feldspar Oligoclase	Colorless, Yellow, Light Green, Emerald-Green, Pink To Violet, Purple, White, Gray	6 - 6½	2.62 - 2.65	Translucent to Opaque	Common	India, Canada, Madagascar, Norway, Russia and United States	Sodium calcium aluminum silicate	Sunstone is very similar in habit to Aventurine, a form of Quartz that exhibits the same glittering Aventurescence effect. Sunstone is occasionally called 'Aventurine Feldspar' to distinguish it from its Quartz counterpart. However, Sunstone is always an orange or reddish color.
559	SUNPYRITE									Please see pyrite
560	SWIRL JASPER									Please see Jasper
561	SWAROVSKI CRYSTALS	Synthetic Stone								Swarovski is the luxury brand name for the range of precision-cut lead crystal glass and related products produced by Swarovski AG of Wattens, Austria. The Swarovski Crystal range includes crystal sculptures and miniatures, jewelry and couture, home decor and chandeliers.
562	SWIRL JASPER									Please see Jasper
563	SYLVANITE	Metal	Grey, white, pale yellow silver-white	1½ - 2	8.16	Opaque	Common	Portugal, Romania, Saudi Arabia, Sweden, South Korea	Silver Gold Telluride	Sylvanite is one of the few minerals that is an ore of gold, besides native gold itself. The element gold is typically either found as native gold (in its elemental state), as an alloy with other metals such as silver and copper and as trace amounts in a few minerals.
564	SYNTHETIC STONES	Synthetic Stone	Colorless, purple, gray-white, grey, yellow-brown, yellow, pink, green	Varies	Varies	Varies	Very Common	Greece, Greenland, Hungary, India, Ireland, Italy, Jamaica, Japan, Kazakhstan		The dream of mankind to produce artificial stones that are really the same as the natural gemstone was realized at the end of the 19th century. The French chemist A. V. Verneuil succeeded in 1888 in synthesizing rubies at commercial prices. In fact, 50 years earlier the first gemstones had been produced synthetically, but they were only of scientific interest.
565	TALC	Clay	Green, Grey, White, Silve	1	2.7 - 2.8	Translucent	Very Common	USA, Austria, Italy	Magnesium Silicate Hydroxide	Talc is an important industrial mineral. Its resistance to heat, electricity and acids make it an ideal surface for lab counter tops and electrical switchboards.
566	TANTALITE	Oxide minerals	Dark black, iron-black, dark brown, red-brown	6 - 6.5	5.918	Opaque	Uncommon	Malawi, Namibia, Mozambique, Norway	Iron Manganese Tantalum Niobium Oxide	The mineral group tantalite is the primary source of the chemical element tantalum. It is chemically similar to columbite, and the two are often grouped together as a semi-singular mineral called coltan or "columbite-tantalite" in many mineral guides.
567	TANZANITE	Zoisite	Blue, intense violet	6½ - 7	3.35	Transparent	Uncommon	Tanzania	Calcium Aluminum Silicate Hydroxyide	The name tanzanite was introduced by the New York jewelers Tiffany 7 Co. In good quality the color is ultramarine to sapphire blue, in artificial light, it appears more amethyst violet.
568	TEKTITES		Green	5.5-0	2.34-2.51					Tektites are gravel-sized bodies composed of black, green, brown, or gray natural glass formed from terrestrial debris ejected during meteorite impacts.
569	TELLURIUM	Selenium	Tin-white, metallic silver	2 - 2½	6.1 - 6.3	Opaque	Uncommon	Honduras, Norway, Spain, Turkey, Uzbekistan, Zimbabwe	Tellurium	Tellurium is extremely rare, one of the nine rarest metallic elements on Earth. It is in the same chemical family as oxygen, sulfur, selenium, and polonium
570	TETRAHEDRITE	Tetrahedrite	Steel to iron grey, black, pink	3½ - 4	4.97	Opaque	Uncommon	Egypt, Eritrea, Ethiopic, Fiji, Finland, Germany	Copper Iron Sulfides	Tetrahedrite is named for its common crystal form, the tetrahedron. The tetrahedron is an interesting isometric crystal form.
571	THENARDITE	Sulfate mineral	Colorless, light grey, light brown	2½ - 3	2.664	Translucent to Opaque	Uncommon	Iceland, Kenya, Namibia, Netherlands, Niger	Sodium Sulfate	Thenardite is one of several non-marine evaporite Sulfate Class minerals. It is easily dissolvable in water and specimens should be stored with desiccant. Thenardite, which is named for the French chemist Louis J. Thenard
572	THOMSONITE	Zeolite	White, Yellow, Pink, Red-Green, Brown and Green	5 - 5.5	2.23 - 2.29	Transparent to Translucent	Uncommon	India, Germany, Italy, USA	Sodium Calcium Aluminosilicate Hydrate	Thomsonite is the name of a series of tecto-silicate minerals of the zeolite group. Prior to 1997, thomsonite was recognized as a mineral species,
573	THULITE	Zoisite	Pink	6.5	3.1-3.38	Opaque	Very Common	Australia, Canada, China, Germany, Worldwide	Calcium Aluminum Silicate Hydroxyide	Thulite (sometimes called rosaline) is a translucent, crystalline or massive pink manganese-bearing variety of the mineral zoisite.
574	TIFFANY									Tiffany Stone" is an unusual material found as mineralized nodules in a beryllium tuff at the site of the Brush-Wellman beryllium mine. It is thought to be an opalized fluorite. Tiffany Stone is also known as "bertrandite" and "ice cream opal."
575	TIFFANY OPAL									Please see Opal
576	TIGER EYE	Quartz	Gold-yellow, gold-brown	6½ - 7	2.58 - 2.64	Opaque	Common	South Africa, Australia, Burma, India, Namibia, United States	Sodium Iron Magnesium Silicate Hydroxyide	Tiger Eye typically displays stripes, because included fibers are crooked or bent. It is sensitive to acids. Found together with hawk's eye in slabs of a few inches thickness.
577	TIGER IRON	Jasper	Light to dark brown, red-gold	6½ - 7	2.64 -2.71	Opaque	Common	South Africa, Australia	Iron Oxide	Tiger iron is an altered rock composed chiefly of tiger's eye, red jasper, and black hematite. The undulating, contrasting bands of color and luster make for an attractive motif, and it is mainly used for jewelry-making and ornamentation.
578	TIGER IRON									with matrix
579	TIGER'S EYE									Tiger's Eye with matrix
580	TIN	Metal	White, metallic silver, black, dark brown	1½ - 2	7.31	Opaque	Very Common	Nigeria, Sweden, The Moon, Uzbekistan, South Korea	Tin	Tin is classified as a metalloid, as its chemical properties fall between those of metals and non-metals, just as the semiconductors silicon and germanium do. It resists corrosion from distilled, sea and soft tap water, but can be attacked by strong acids, alkalis, and acid salts.
581	TINCALCONITE		white	1	1.88	Opaque	Common	Searles Lake, San Bernardino Co., California	Hydrous sodium borate	Most Borax specimens lose water in their structure if stored in dry areas and alter to Tincalconite. Although Tincalconite is found in a natural state, almost all specimens were transformed from Borax after being taken from the mine.
582	TINGUAITE	Igenous Rock	Pale- to Dark-Green	5.5	2.56 - 2.66	Translucent to Opaque	Uncommon	Rio De Janero, United States	Metamorphosed peri-aluminous	Tinguaite is an uncommon extrusive igneous rock, volcanic rock, of intermediate chemical composition between felsic and mafic, with texture ranging from aphanitic (fine-grain) to porphyritic (mixed fine- and coarse-grain).
583	TITANITE	Silicates	Light to dark brown, orange, yellow, yellowish-green, olive-green, emerald-green, greenish-brown	5 - 5.5	3.4 - 3.6	Transparent to opaque	Uncommon	Austria, Italy, Switzerland, Russia, Africa, Brazil	Calcium titanium silicate	Titanite is frequently called by the name Sphene, which was the more popular term for this mineral prior to 1982. In 1982, the IMA adopted the official name as Titanite and discredited Sphene.
584	TITANIUM	Metal	Silver-grey	4	4.506	Opaque	Uncommon	China, Russia	Titanium	Titanium is also called the “space age metal”, it has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color. Titanium can be alloyed with iron, Aluminum, vanadium, molybdenum, among other elements, to produce strong lightweight alloys.
585	TOOLS / HARDWARE									The mechanical equipment necessary for conducting an activity, usually distinguished from the theory and design that make the activity possible.
586	TOPAZ	Topaz	Colorless, yellow, red-brown, light blue, pink-red, violet, light green	8	3.49 - 3.57	Transparent	Common	Brazil, Afghanistan, Burma, China, Japan, Madagascar, Mexico, Namibia, Nigeria, Pakistan, Russia, Zimbabwe, Sri Lanka	Hydroxyy silicate of aluminum with fluorite and iron	The name topaz is most probably derived from a place of discovery on an island in the Red Sea, now ‘Zebirget’ but formerly ‘Topazos’. Colors of gemstone that is today called topaz are rarely vivid.
587	TOUCHSTONE (KASAUTI STONE)									A black siliceous stone related to flint and formerly used to test the purity of gold and silver by the streak left on the stone when rubbed by the metal.
588	TOURMALINE	Tourmaline	Colorless, pink, red, yellow, brown, green, blue, violet, black, multicolored	7 - 7½	2.82 - 3.32	Translucent to Opaque	Common	Sri Lanka, Western and Central Europe	Complex Silicate	Tourmaline has been known since antiquity in the Mediterranean region, the Dutch imported it only in 1703 from Sri Lanka to Western and Central Europe. They gave the new gemstones a Sinhalese name, 'Turamali' which is thought to mean "stone with mixed colors".
589	TRANSPORTATION
590	TRAVERTINE	Calcite	Golden honey, silvery green	2.5 - 3.5	2.71	Opaque	Uncommon	USA	Calcium Carbonate	A variety of Calcite. Travertine is formed by calcium carbonate dissolving in ground water and then being deposited on the earth’s surface by rivers, natural springs, or geysers. Often it is banded or layered and in pastel shades of almost any color.
591	TRONA	Thermonatrite-Natron	Colorless, grey-white, light yellow	2½	2.14	Transparent to Translucent	Uncommon	Chad, Kenya, Libya, Switzerland, Tanzania, Turkey, Venezuela, USA	Hydrated Sodium Carbonate	Trona is mined as the primary source of sodium carbonate in the United States, where it has replaced the Solvay process used in most of the rest of the world for sodium carbonate production.
592	TSAVORITE	Garnet	Yellow, green with blue	7.25-7.5	3.84	Transparent to Translucent	Uncommon	Kenya, Madagascar, Tanzania	Calcium Aluminum Silicate	Tsavorite is one of two green varieties of garnet, though arguably the more important of the two. Especially in smaller sizes, tsavorite creates competition for emerald because it is less included, rarely treated, and more durable.
593	TSCHERMIGITE	Alum	White, Colorless	1.5-2	1.65	Translucent	Uncommon	Bohman, Czech Republic	Ammonium Chloride	Tschermigite is a mineral form of ammonium alum, formula. It is found in burning coal seams, bituminous shale and fumaroles. Because of its extreme water solubility it is unlikely to persist except in the dryest of conditions.
594	TUNGSTEN
595	TURQUOISE	Turquoise	Sky-blue, blue-green, apple-green	5 - 6	2.31 - 2.84	Translucent to Opaque	Uncommon	Afghanistan, Argentina, Australia, Brazil, China, Israel, Mexico, Tanzania and United States	Hydrous Copper Aluminium phosphate	The name turquoise means "Turkish stone' because the trade route that brought it to Europe used to come via Turkey.
596	TURQUENITE									Please see Howlite. Turquonite is howlite that is dyed blue to resemble turquoise, and is often falsely sold as turquoise.
597	TUZLAITE	Monoclinic	White, colorless	2 - 3	2.21	Transparent	Uncommon	Bosnia and Herzegovina, Germany	Hydrated Sodium Calcium Borate Hydroxyide	Tuzlaite is a monoclinic-prismatic mineral containing boron, calcium, hydrogen, oxygen, and sodium.
598	UNAKITE	Granite	Colorless, pink, green	6 - 7	2.6 - 2.7	Opaque	Common	USA, Brazil, South Africa, Sierra Leone	Orthoclase Feldspar	Unakite is an altered granite composed of pink orthoclase feldspar, green epidote, and generally colorless quartz. It exists in various shades of green and pink and is usually mottled in appearance. A good quality unakite is considered a semiprecious stone.
599	URANINITE	Uraninite	Black, dark brown, grey, green, green-grey	5 - 6	10.63 - 10.95	Opaque	Uncommon	Argentina, Brazil, Bulgaria, Gabon, India, Madagascar, Mozambique	Uranium Oxide	All uraninite minerals contain a small amount of radium as a radioactive decay product of uranium
600	URANOFANO
601	URANIUM	Metal	Black, dark brown	6	19.1	Transparent to Opaque	Uncommon	Australia, Kazakhstan, Canada	Uranium	It occurs naturally in low concentrations (a few parts per million) in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite.
602	UVARORITE	garnet	Green, emerald-green, green-black	6½ - 7	3.77 - 3.81	Transparent, Translucent	Uncommon	Finland, Iran, Norway,Spain, Russia,	Nesosilicate	Uvarovite is one of the rarest of the garnet group minerals, and is the only consistently green garnet species, with an emerald-green color. It occurs as well-formed fine-sized crystals.
603	VANADINITE	Pyromorphite	Orange-red, brown, yellow, pale straw-yellow, colorless	2½ - 3	6.88	Transparent	Uncommon	Chile, Gabon, Kazakhstan, Span, Tunisia, Uzbekistan, Zambia, Mexico	Lead Chlorovanadate	Vanadinite is an uncommon mineral, only occurring as the result of chemical alterations to a pre-existing material. It is therefore known as a secondary mineral. It is found in arid climates and forms by oxidation of primary lead minerals.
604	VANADIUM									Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery gray, ductile and malleable transition metal. The element is found only in chemically combined form in nature.
605	VARISCITE	Variscite	Pale, emerald-green, blue- green, colorless	3½ - 4½	2.57 - 2.61	Opaque	Uncommon	Colombia, Germany, Ireland, Kazakhstan, Malaysia, Portugal, Senegal, Sweden, Venezuela	Hydrated Aluminum phoshate	Variscite is a relatively rare phosphate mineral. It is sometimes confused with turquoise; however, variscite is usually greener in color. Variscite is sometimes used as a semi-precious stone, and is popular for carvings and ornamental use.
606	VERDITE	Fuchsite	Light to dark green	3	2.80 - 3.0	Translucent to Opaque	Uncommon	Africa, Toba, Japan	Hydroxy Fluorite silicate of potassium and aluminum	Verdite is a trade name for two green stones found in Africa: Serpentine and Fuchsite. Commonly used for sculptures; increasingly also for costume jewelry.
607	VESZELYITE		Green, blue, greenish blue, dark blue;	3.5-4	3.4	Translucent		Moravicza (Vasko) in the Banat, Romania		A rare secondary Cu-Zn mineral occurring in the oxidised zones of base metal deposits.
608	VESUVIANITE	TERRAGONAL	Brown, yellow, brown-black, light green, emerald green, white, red, purple, violet, blue-green to blue	6.5	3.35 - 3.45	Subtransparent to subtranslucent	Uncommon	Somma, Vesuvius, Italy	Sorosilicate	Vesuvianite, also known as idocrase, is a green, brown, yellow, or blue silicate mineral. Vesuvianite occurs as tetragonal crystals in skarn deposits and limestones that have been subjected to contact metamorphism.
609	VESONITE									Please see vesuvianite.
610	VIOLANE	Diopside	Violet, Light Blue	5 - 6	3.22 - 3.40	Translucent to Opaque	Uncommon	Greece, Italy, USA	Calcium Magnesium Manganese Silicate	Violane is a coarse violet to light blue, manganese-rich variety of Diopside. It is translucent to opaque material from Piedmont, Italy. Violane is used for ornamental objects.
611	VIOLET STONE									Please see Violane
612	VIVIANITE	Phosphate	Light green, dark blue, colorless	1.5-2	2.68	Transparent to Translucent	Common	UK, USA, Africa, Australia, South America	Hydrated Iron Phosphate	Vivianite is a hydrated iron phosphate mineral found in a number of geological environments. Pure fresh vivianite is colorless, but the mineral oxidizes very easily.
613	VLASOVITE	Sillicate	Colorless or brownish	6	2.92 - 2.97	Transparent to Translucent	Uncommon	Canada, Russia, Saint Helena	Sodium Zircon Sulfur Iodine Hydroxide	Vlasovite is a rare inosilicate (chain silicate) mineral with sodium and zirconium. It was discovered in 1961 at Vavnbed Mountain in the Lovozero Massif, in the Northern Region of Russia.
614	VOLCANIC COTTAM
615	WATER									Water is a common chemical substance that is essential for the survival of all known forms of life. In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam.
616	WAVE JASPER	Chalcedony	Red, yellow, brown, green, blue	6½ - 7	2.58 - 2.91	Opaque	Common	Egypt, Australia, Brazil, India, Canada, Kazakhstan, Madagascar, Russia	Silicon Dioxide	The appeal of Jasper is its interesting color patterns and formations. Though it can be a solid color, it is most often mottled, spotted, ringed, or striped. Each Jasper has a unique color or pattern, lending this gemstone much variety.
617	WAVELLITE	Phosphate	Green to yellowish-green and yellow, greenish white, yellowish-brown, brown, brownish-black, blue	3.5 - 4	2.36	Transparent to opaque	Common	England, USA	Aluminum phosphate	A secondary mineral found most often in aluminous, low-grade metamorphic rocks. Usually found as radiating "starburst" clusters of green to yellow-green fibrous crystals on fracture surfaces in the matrix,
618	WHITE BONE									See Fossil
619	WHITE CORAL									Please see Coral
620	WHITE TOPAZ									Please see Topaz
621	WILLEMITE	Phenakite	Colorless, white, pastel green, apple-green, light blue	5½	3.89 - 4.19	Opaque	Uncommon	Ireland, Mongolia, Norway, Portugal, Tajikistan, Ukraine, Zambia	Zinc Silicate	Willemite is a zinc silicate mineral and a minor ore of zinc. It is highly fluorescent (green) under shortwave ultraviolet light. It occurs in all different colors in daylight, in fibrous masses, solid brown masses ("troostite"), and apple green gemmy masses.
622	WOLFRAMITE	Tungstates	Black, dark brown	5 - 5½	7.1 - 7.6	Translucent to Opaque	Common	India, Japan, Morocco, Namibia, Mongolia, Mexico, New Zealand, Niger, Nigeria	Iron Manganese Tungstate	Wolframite was highly valued as the main source of the metal tungsten, a strong and quite dense material with a high melting temperature used for electric filaments and armor-piercing ammunition, as well as hard tungsten carbide machine tools.
623	WOLLASTONITE	Calcium Inosilicate	White, colorless or gray	4.5 - 5	2.86 - 3.09	Transparent to Translucent	Common	Romania, Italy, Finland, USA, China, India	Calcium Silicate	Wollastonite is a calcium inosilicate mineral that may contain small amounts of iron, magnesium. It forms when impure limestone or dolostone is subjected to high temperature and pressure sometimes in the presence of silica-bearing fluids
624	WOOD									Wood is an organic material; in the strict sense it is produced as secondary Sytem in the stems of trees.
625	WOOD OPAL									Please see Opal
626	WULFENITE	Scheelite	Honey-yellow, orange, red	3	6.50 - 7.00	Transparent to Translucent	Uncommon	China, Greece, Greenland, Hungary, Iran, Ireland, Italy, Japan, Kazakhstan	Lead Molybdate	Stubby, pyramidal crystal, often tabular and with a square outline. A secondary ore of molybdenum. Much sought after by collectors.
627	WYOMING JADE									Please see Jade
628	YELLOW LACE AGATE									Please see Agate
629	YELLOW METAL									Please see Metal
630	YELLOW QUARTZ									Please see Quartz
631	YELLOW TOPAZ	Topaz	Colorless, yellow, red-brown, light blue, pink-red, violet, light green	8	3.49 - 3.57	Transparent	Common	Brazil, Afghanistan, Burma, China, Japan, Madagascar, Mexico, Namibia, Nigeria, Pakistan, Russia, Zimbabwe, Sri Lanka	Hydroxyy silicate of aluminum with fluorite and iron	The name topaz is most probably derived from a place of discovery on an island in the Red Sea, now ‘Zebirget’ but formerly ‘Topazos’. Colors of gemstone that is today called topaz are rarely vivid.
632	YUGAWARALITE	Zeolite	White to Milky White	2	2.2-2.23	Transparent to Translucent	Uncommon	India, Japan, USA	Calcium Aluminosilicate Hydrate	Named after its discovery locality, Yugawara Hot Spring, Kanagawa Prefecture, Japan. A few colorless faceted gemstones have been cut from this exceptional and extremely rare material.
633	ZEBRA JASPER	Chalcedony	White, light yellow	7	2.58-2.91	Opaque	Uncommon	South Africa	Silicon Dioxide	The Zebra Stone is a stone composed of characteristics similar to Tiger Iron and Tiger Eye. Colors vary from dark rich browns streaked with grey to a lighter brown brushed with a cream color and some materials have shriller, like Tiger Eye.
634	ZEBRATO GRANITE									Please see Granite.
635	ZINC	Metal	White metallic	2	6.9 - 7.2	Opaque	Uncommon	Guinea, Italy, Mongolia, The Moon, Russia	Zinc	Zinc is an essential mineral of "exceptional biologic and public health importance". Zinc deficiency affects about 2 billion people in the developing world and is associated with many diseases.
636	ZINNWALDITE	Phyllosilicate mineral	Grey-brown, yellow-brown, light violet, pink, silver-grey, green-grey, nearly black	2½ - 4	2.9 - 3.02	Translucent to Opaque	Uncommon	Egypt, Greenland, Japan, North Korea, South Africa, Tajikistan, Zimbabwe	Potassium Lithium Iron Aluminum Silicate Hydroxyide Fluoride	Zinnwaldite, is a potassium lithium iron Aluminum silicate Hydroxyide fluoride silicate mineral in the mica group. It occurs in greisens, pegmatite, and quartz veins often associated with tin ore deposits.
637	ZIRCON	Zircon	Colorless, yellow, grey, red-brown, green, brown, black,	7½	4.6 - 4.7	Transparent to Translucent	Common	Angola, Antarctica, Armenia, Bangladesh, Barbados, Bulgaria, Cuba, Eritrea, Gabon, Ghana, Guinea, India	Zirconium Silicate	Zircon is a mineral belonging to the group of nesosilicates. zircon varies between colorless, yellow-golden, red, brown, and green. Colorless specimens that show gem quality are a popular substitute for diamond.
638	ZOISITE	Zoisite	Colorless, purple, grey-white, yellow-grey, brown, yellow, pink, green	6 - 7	3.15 - 3.36	Transparent to Opaque	Uncommon	Greece, Greenland, Hungary, India, Ireland, Italy, Jamaica, Japan, Kazakhstan, Madagascar, Mexico	Hydroxyy silicate of calcium and aluminum	Zoisite is a grayish-white or grayish-green crystalline mineral of the epidote group consisting of a Hydroxyyl silicate of calcium and aluminum. It is popular among scientist and collectors.

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Gemstone & Mineral Guide