Gemstone Chart |
Natural Freshwater Pearl Freshwater pearls are a kind of pearl that comes from freshwater mussels.Freshwater pearls come in many shapes from round to button shapes, from flat flakes to rice shapes and in many colors. As with the salt water Akoya pearl the round shapes are generally more expensive. Color: orange, pink, white, gray, light purple, rose, black, brown, gold, yellow, silvery, green, blue, bronze. Categories: semi-precious stone Chemical Composition: CaCO3 Crystal Group: Not applicable Hardness: 3.5 - 4.0 Density: 2.66 ¨C 2.78+ Occurrence: China, Japan
| Natural Jadeite A rare, usually green mineral of the pyroxene group. Jadeite can also occur in white, auburn, buff, or violet varieties. The most highly valued form of jade consists of jadeite.Jade has a history in China of at least four thousands years.Experts believe that, although more expensive, diamonds and gold cannot be compared with jade - jade is animated with a soul. Color: Pure white thru pink, brown, red, orange, yellow, mauve, violet, blue, and black, to an extensive range of green and mottled green and white. Categories: semi-precious stone Chemical Composition: NaAl(SiO3)2 Crystal Group: Monoclinic Refractive Index: 1.654 - 1.667 Hardness: 7 Density: 3.32 Occurrence: Northern Myanmar. Non commercial discoveries of Jadeite have also been reported in China; Russia (in the Polar Urals); Niigata, Japan; San Benito County, California, USA, and Guatemala.
| Natural Lapis Lazurite is a popular but generally expensive mineral. Well-formed, deep blue crystals are rare and valuable. Lapis lazuli is a gemstone of the kind that might have come straight out of the Arabian Nights: a deep blue with golden inclusions of pyrites which shimmer like little stars. Color: Blue, greenish-blue, violet blue Categories: semi-precious stone Chemical Composition: A complex aggregate Crystal Group: Not applicable Refractive Index: 1.5 Hardness: 5.5 Density: 2.7-2.9 Occurrence: Afganistan, Pakistan, Chile, Russia, U.S.A., Angola, Burma
| Natural Rhodochrosite Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO3. The pink color of rhodochrosite is caused by the element manganese and it is formed when manganese is dissolved by ground water and combines with a carbonate material and then drips off the ceiling of caves and crevices deep underground.Rhodochrosite often forms pink and white bands. It is often carved into figurines or boxes while the tubular stalactite formations are often sliced for use in jewelry. Fine gem quality crystals are sometimes cut into gemstones for use in high end jewelry, but the more common grade is used extensively in silver and gold jewelry. Color: Rose red, raspberry red, pink, grey, fawn, brown Categories: semi-precious stone Chemical Composition: MnCO3 Crystal Group: Trigonal Refractive Index: 1.600 ¨C 1.820 Hardness: 4 Density: 3.45 ¨C 3.70 Occurrence: Argentina; Colorado, U.S.A.; Romania; Hungary; India; South Africa; Saxony, Chile; Peru; Mexico.
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