Gemstone Chart |
Natural Alexandrite Alexandrite was discovered in 1830 in the Ural mountains of Russia. Alexandrite is also found in Sri Lanka, Brazil, India, Tanzania, Zimbabwe, and most recently in Madagascar. The alexandrite variety of chrysoberyl is one of the rarest and most sought after of all gems. Color: changing from green to red Categories: semi-precious stone Chemical Composition: BeAl2O4 Crystal Group: Orthorhombic Refractive Index: 1.741 - 1.760 Hardness: 8.50 Density: 3.73 Occurrence: Tanzania, India, Russia, Madagascar, Sri Lanka, Zimbabwe, Zambia
| Natural Beryl Beryl is a semi-precious clear gemstone which usually comes in greens, yellows, and occasionally pinks, ands various shades thereof. Color: Green, blue, pink, yellow, red Categories: semi-precious stone Chemical Composition: Be3Al2(SiO3)6 Crystal Group: Hexagonal Refractive Index: 1.577(+-.016), 1.583 (+-.017) Hardness: 7.5 Density: 2.67-2.745 Occurrence: Austria, Columbia, Brazil, Russia, East Africa, Australia, Madagascar, South Africa, Zimbabwe, India, Pakistan, Zambia, Nigeria, U.S.A., Afghanistan
| Natural Euclase Euclase is a rare mineral, resembling beryl in color and hardness.Euclase is found in granitic pegmatites with other gem minerals such as topaz and beryl. Color: White, pale blue, greenish blue, dark blue. Categories: semi-precious stone Chemical Composition: BeAlSiO4(OH) Crystal Group: Monoclinic Refractive Index: 1.652-1.672 Hardness: 7.5 Density: 3.18 Occurrence: Brazil, Tanzania, Russia, Zimbabwe, Madagascar, Austria.
| Natural Rhodolite Rhodolite is a beautiful pink to violetish red garnet which was named after the rhododendron flower. Commercially rhodolite is one of the most important garnets. Rhodolite is quite available in small sizes which are relatively low in price. Very fine large rhodolite garnets are rare and are moderate in price. Color: red, purple-red Categories: semi-precious stone Chemical Composition: Al2(SiO4)3 Crystal Group: Cubic Refractive Index: 1.75 - 1.77 Hardness: 7.25 Density: 3.74 - 3.94 Occurrence: Brazil, East Africa, Ceylon, India, Madagascar, Zimbabwe
| Natural Topaz Topaz is a silicate mineral most often found in igneous rocks of felsic composition. It is a common gemstone that has been used for centuries in jewelry. Gem quality topaz most commonly occurs in nature as a colorless crystal. It is a very popular gemstone. Color: colorless, blue, yellow-brown, pinkish orange, red-orange, red-brown, tan. Categories: semi-precious stone Chemical Composition: AL(F,OH)2SIO4 Crystal Group: Orthorhombic Refractive Index: 1.629 - 1.637 Hardness: 8 Density: 3.52 - 3.56 Occurrence: Brazil, Sri Lanka, Nigeria, Germany, Australia, Japan, Russia, Ireland, Zimbabwe.
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