Gemstone Chart |
Natural Actinolite Actinolite is a natural mineral with the chemical formula Ca2(Mg,Fe)5Si8O22(OH)2.the crystals have a hardness of 5.5 on Moh’s scale, and there are two directions of cleavage. Natural actinolite is semi-precious to precious stone used in jewelry and other adornments. Color: Green, Brown Categories: semi-precious stone Chemical Composition: Amphibole Group Crystal Group: Monoclinic Refractive Index: 1.620 - 1.642 Hardness: 5.5 Density: 3.05 Occurrence: Tanzania
| 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 Malaia Garnet Malaia garnet is a mixture of almandine, pyrope, and spessartine. It has remained the preserve of collectors for the 2 decades since it was discovered, mainly due to its extreme rarity.Tanzania is the known source for this lovely gemstone. Color: orangey pink, champagne, orange brown, copper-pink. Categories: semi-precious stone Chemical Composition: [Mg3 + Mn3]AL2(SIO4) Crystal Group: Cubic Refractive Index: 1.73 - 1.81 Hardness: 7 - 7.5 Density: 3.65 - 4.20 Occurrence: Kenya, Tanzania, Madagascar
| Natural Pezzottaite Pezzottaite is a raspberry-red to pink member of the Beryl Group named after Dr. Federico Pezzotta. Discovered in Madagascar and IMA approved in 2003. It is one of the great new gem discoveries of the last 20 years. Categories: semi-precious stone Crystal Group: Trigonal Refractive Index: 1.604 - 1.615 Density: 3.1 Occurrence: Madagascar, Afghanistan
| 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
| 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.
| Natural Tanzanite Tanzanite is a rare gem which has been celebrated as one of the most exciting finds of the 20th century. Manuel D’Souza discovered the gem in 1967 in Tanzania. Because tanzanite is relatively soft, it is not usually set in necklaces and earrings, so the tiara is truly a rarity. Color: Blue, Blue Purple, Green, Pink. Categories: semi-precious stone Chemical Composition: Ca2(Al,OH)Al2(SIO4) Crystal Group: Orthorhombic Refractive Index: 1.688 - 1.707 Hardness: 6-7 Density: 3.30 (+.10, -.10) Occurrence: Tanzania
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