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 Clinohumite Clinohumite is a rare mineral and an especially rare gemstone. It is a member of the humite group of minerals, which includes humite, clinohumite, chondrodite, and norbergite.Only two sources of gem-quality material are known: the Pamir Mountains of Tajikistan, and the Taymyr region of northern Siberia. Color: Brown, yellow, white, orange, or reddish brown Categories: semi-precious stone Chemical Composition: Magnesium Silicate Fluoride OH Crystal Group: Monoclinic Refractive Index: 1.625 ¨C 1.668 Hardness: 6 - 6.5 Density: 3.17 - 3.35 Occurrence: Extremely rare - gem quality found only in the Pamir Mountains, Tadzhikistan. Other mineralogical occurrences include, Mt. Vesuvius, Italy; Pargas, Finland; Llanos de Juanar, Malaga, Spain; Tilly Foster Mine, New York; Fort Defiance, Apache County, Arizona; Crestmore Quarry, Riverside County and Lower Lake, Fresno County, California; Luna, New Mexico and Franklin, New Jersey, USA.
| 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 Phenakite phenakite is a fairly rare nesosilicate mineral consisting of beryllium orthosilicate, It is one of the brightest of the colorless gemstones.Madagascar seems to be the most important source for this rare stone. Color: White Categories: semi-precious stone Chemical Composition: Be2SiO4 Crystal Group: Hexagonal Refractive Index: 1.651-1.696 Hardness: 7.5-8.0 Density: 2.94--2.96 Occurrence: Russia, Madagascar, U.S.A., Brazil, France, Switzerland, Ceylon, E. Africa.
| 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 Sphene Sphene is also known as calcium titanium silicate.It is named from the greek word for wedge, because of its typical wedge shaped crystal habit.Because of it's high dispersion and refractive index, a well cut sphene can display stunning brilliance. Sphene is somewhat soft and as a result is more suitable as a pendant than as a ring stone. Sphene is rarely very clean. Color: Green, yellow. brown Categories: semi-precious stone Chemical Composition: CaTiSiO5 Crystal Group: Monoclinic Refractive Index: (1.885-1.990,)-(1.915-2.050) Hardness: 5.5 Density: 3.52-3.54 Occurrence: Austria, Dheirene-Madagascar, India, USA, 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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