Gemstone Chart |
Natural Apatite Apatite displays strong fluorescence under short wave ultra-violet light. There is a particularly intense and deeply saturated, geenish-blue (aka swiss blue) variety from Madagascar known as "Neon Apatite" that is becoming quite popular in the gem trade. Color: yellow, green, below, violet Categories: semi-precious stone Chemical Composition: Phosphate group Crystal Group: Hexagonal Refractive Index: 1.63-1.64 Hardness: 5 Density: 3.17-3.23 Occurrence: Burma, Ceylon, Madagascar, Mexico, Canada, India
| 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 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 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.
| Natural Spinel Spinel is the magnesium aluminium member of the larger spinel group of minerals. It has the formula MgAl2O4.Pure spinel is white, but impurities give it a wide range of colors.Almost all colors are used in jewelry, but the most valuable and popular color is the deep red. Spinel is cut into gems for use as jewelry. The deep-red variety, known as ruby spinel, is the most prized form. Color: orange, pink, black, blue, lavender, mauve, greenish blue, and vivid red Categories: semi-precious stone Chemical Composition: MgAl2O4 Crystal Group: Cubic Refractive Index: 1.718 (-.006,+.044) Hardness: 8 Density: 3.60 (-.03, +.30) Occurrence: Mogok, Burma; Sri Lanka; Amboseli district, Kenya; Jemaa district, Nigeria; Matombo, Umba, and Tunduru Tanzania; Hunza, Pakistan; Pamir range, Tajikstan; Luc Yen, Vietnam; Madagascar; Australia; Sweden; Brazil.
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