Gemstone Chart |
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.
| Natural Turquoise Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium.The gem turquoise owes it's beauty almost entirely to its superb color. It has been used for ornamentation since 3000BC and possibly before. Color: Blue, Greenish Blue Categories: semi-precious stone Chemical Composition: CuAl6(PO4)4(OH)85H2O Crystal Group: Triclinic Refractive Index: 1.62 Hardness: 5.5-6 Density: 2.60- 2.90 Occurrence: Iran, USA, India, Tibet, China, Egypt, Chile, Russia, Australia
| Natural Zircon Zircon is a mineral belonging to the group of nesosilicates. It is one of the heaviest gemstones, which means that it will look smaller than other varieties of the same weight. Zircon occurs in a wide range of colours,the most popular colour is blue zircon. The wide variety of colours of zircon, its rarity, and its relatively low cost make it a popular collector's stone. Color: Brown, blue, red, orange, white, green Categories: semi-precious stone Chemical Composition: ZrSiO4 Crystal Group: Tetragonal Refractive Index: 1.780-1.984 Hardness: 7.5 Density: 4.00-4.73 Occurrence: Ceylon, Burma,France, Norway, East Africa,Australia, SE Asia.
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