Gemstone Chart |
Natural Andalusite Andalusite is popular as a collector stone but is seldom used in jewelry probably because of it's unavailability. With a hardness of 7 - 7.5 andalusite is tough enough to be used in jewelry. Andalusite, especially in the rough, can easily be confused with alexandrite because of similarities in color Categories: semi-precious stone Chemical Composition: Al2SiO5 Crystal Group: Orthorhombic Refractive Index: 1.628 - 1.647 Hardness: 7 - 7.5 Density: 3.13 - 3.21 Occurrence: Brazil, Sri Lanka, Spain, East Africa, Burma, U.S.A.
| Natural Danburite Danburite is a very spiritual stone that carries a pure vibration. With a hardness of 7, danburite is quite hard and suitable for any kind of jewelry. Danburite handles easily and ordinarily offers no problems for lapidaries. It makes an especially brilliant gem because of its extreme clarity. Color: White, yellowish, very light pink, buff colored, very light brown Categories: semi-precious stone Chemical Composition: calcium borosilicate Crystal Group: Orthorhombic Refractive Index: 1.630(+.003,-.003) - 1.636 (+.003, -.003) Hardness: 7 Density: 3 Occurrence: Danbury, Connecticut and Russell, New York, USA; Charcas, San Luis Potosi, Mexico; Kyushu Island, Japan; Mogok, Burma and Uri, Switzerland; Madagascar.
| 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 Iolite Iolite is a popular and interesting gemstone, and is the gem variety of the mineral cordierite.It has also been called water sapphire because it looks very much like a blue sapphire. Color: violet, blue, dark blue, Categories: semi-precious stone Chemical Composition: MG2AL4SI5O18 Crystal Group: Orthorhombic Refractive Index: 1.53 - 1.55 Hardness: 7 - 7.5 Density: 2.57 - 2.66 Occurrence: Sri Lanka; Burma; India; Tsivory,Madagascar; Canada; Namibia; Tanzania; Norway; U.S.A.; Brazil
| Natural Peridot Peridot is the best known gem variety of olivine, a species name for a series of magnesium-iron rich silicate minerals.It is one of the prettiest of all green gems.Most peridot formed deep inside the earth and was brought to the surface by volcanoes. Some has also come to Earth in meteorites, but this extraterrestrial peridot is extremely rare, and you're not likely to see it in a retail jewelry store. Color: Green, olive. Categories: semi-precious stone Chemical Composition: (Mg,Fe)2(SiO)4 Crystal Group: Orthorhombic Refractive Index: 1.654-1.689 Hardness: 6.5 Density: 3.34 Occurrence: China, Burma, East Africa, U.S.A., and Vietnam
| Natural Prehnite Prehnite is a hydrated calcium aluminum silicate that occurs in a soft yellow-green to apple-green color.It was a rare gemstone, most prehnite is translucent but transparent specimens are sometimes found.While you are unlikely to find it in your local jewelry store, gemstone dealers often have some supply. Deposits are found in South Africa, Australia, China, Scotland and the United States. Color: yellow green, brown, yellow brown, oil green Categories: semi-precious stone Chemical Composition: (CA2Al2SI3O10(OH)2) Crystal Group: Orthorhombic Refractive Index: 1.61 - 1.64 Hardness: 6 Density: 2.80 - 2.95 Occurrence: China, France, U.S.A., Scotland, Australia
| 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
|
|