Gemstone Chart |
Natural Benitoite Benitoite is considered to be a semi-precious gemstone. Very limited in nature and available from only one spot on earth (San Benito County, California), Benitoite is among the 10 rarest gemstones on earth Color: Blue, white, colorless Categories: semi-precious stone Chemical Composition: BaTiSi3O6 Crystal Group: Hexagonal Refractive Index: 1.757 ¨C 1.804 Hardness: 6.5 Density: 3.65 ¨C 3.68 Occurrence: San Benito County, California
| Natural Enstatite Enstatite is a relatively common mineral, but is rarely used for jewelry purposes. It is generally cut for gem connoisseurs and collectors rather than for the common consumer. Color: Gray, green, brown, orange-brown, yellowish-brown, colorless, pale yellow. Categories: semi-precious stone Chemical Composition: MgSiO3 Crystal Group: Orthorhombic Refractive Index: 1.663-1.673 Hardness: 5.5 Density: 3.26-3.28 Occurrence: South Africa, Burma, Tanzania, Sri Lanka, Kenya, Germany, Norway, Greenland
| Natural Fluorite Fluorite has a wide range of colors including yellow, blue, pink purple and green. It is an interesting and beautiful gemstone. Color: Colorless, yellow, brown, green, blue, violet, pink Categories: semi-precious stone Chemical Composition: CaF2 Crystal Group: Cubic Refractive Index: 1.43 Hardness: 4 Density: 3.18 Occurrence: Namibia, U.K., Switzerland, Nigeria, Czechoslovakia, Canada, Poland, Italy, Norway, Germany, U.S.A.
| Natural Grossularite A member of the garnet group, grossularite is found in a variety of colors including, yellow, brown, white, colorless, green, violet-red, and orangey red. Color: Brown, yellow, green Categories: semi-precious stone Chemical Composition: Ca3Al2(SiO4)3 Crystal Group: Cubic Refractive Index: 1.72-1.748 Hardness: 7.25 Density: 3.65 Occurrence: Canada, East Africa, Pakistan, New Zealand, Ceylon, South Africa, U.S.A.
| Natural Hemimorphite Hemimorphite is a usually white or colorless mineral, essentially Zn4Si2O7(OH)2¡¤H2O, an important ore of zinc. Also called calamine. Color: Light blue, dark blue, green ,white. Categories: semi-precious stone Chemical Composition: (Zn4Si2O7(OH)2.H2O) Crystal Group: Orthorhombic Refractive Index: 1.612-1.633 Hardness: 5 Density: 3.44 Occurrence: Franklin and Sterling Hill New Jersey, New Mexico, Montana, Arizona, U.S.A; Congo; Nerchinak in Transbaikalia, Siberia; Zambia; Santa Eulalia and Mapimi, Mexico; England; Wenshan, Yunnan Province, China.
| Natural Oligoclase Oligoclase is a rock-forming mineral belonging to the plagioclase feldspars. Oligoclase is famous for its two gem varieties: Sunstone and Moonstone. Color: green, orange, red, colorless Categories: semi-precious stone Chemical Composition: [Na,Ca]AlSi3O8 Crystal Group: Triclinic Refractive Index: 1.53 - 1.54 Hardness: 6 - 6.5 Density: 2.62 - 2.65 Occurrence: Tvedestrand and Hitero on the south coast of Norway; near Lake Baikal Russia; Ontario, Canada; Tanzania; Kangayam, southern India; France; and in Maine, New Mexico, New York, North Carolina, Pennsylvania, Virginia and Oregon in the USA.
| Natural Phenakite phenakite is a fairly rare nesosilicate mineral consisting of beryllium orthosilicate, It is one of the brightest of the colorless gemstones.Madagascar seems to be the most important source for this rare stone. Color: White Categories: semi-precious stone Chemical Composition: Be2SiO4 Crystal Group: Hexagonal Refractive Index: 1.651-1.696 Hardness: 7.5-8.0 Density: 2.94--2.96 Occurrence: Russia, Madagascar, U.S.A., Brazil, France, Switzerland, Ceylon, E. Africa.
| Natural Sillimanite Sillimanite is an alumino-silicate mineral with the chemical formula Al2SiO5. Sillimanite is a very rare trimorph and it has a common variety called fibrolite. Color: violet blue, grey green, colorless, brown, green, Categories: semi-precious stone Chemical Composition: Al2OSiO4 Crystal Group: Orthorhombic Refractive Index: 1.658 - 1.678 Hardness: 6 - 7.5 Density: 3.25 Occurrence: France, Madagascar, U.S.A., Sri Lanka, Burma. Kenya
|
|