Gemstone Chart |
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 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 Prehnite Prehnite is a hydrated calcium aluminum silicate that occurs in a soft yellow-green to apple-green color.It was a rare gemstone, most prehnite is translucent but transparent specimens are sometimes found.While you are unlikely to find it in your local jewelry store, gemstone dealers often have some supply. Deposits are found in South Africa, Australia, China, Scotland and the United States. Color: yellow green, brown, yellow brown, oil green Categories: semi-precious stone Chemical Composition: (CA2Al2SI3O10(OH)2) Crystal Group: Orthorhombic Refractive Index: 1.61 - 1.64 Hardness: 6 Density: 2.80 - 2.95 Occurrence: China, France, U.S.A., Scotland, Australia
| Natural Quartz Quartz is the most common mineral on the face of the Earth. It is found in nearly every geological environment and is at least a component of almost every rock type.There are many different varieties of quartz, several of which are semi-precious gemstones. Categories: semi-precious stone Chemical Composition: SiO2 Crystal Group: Trigonal Refractive Index: 1.544 - 1.553 Hardness: 7 Density: 2.65
| 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 – 1.820 Hardness: 4 Density: 3.45 – 3.70 Occurrence: Argentina; Colorado, U.S.A.; Romania; Hungary; India; South Africa; Saxony, Chile; Peru; Mexico.
| 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 Rubelite The rubellite is a particularly beautiful gemstone from the colourful family of the tourmalines. Its colour shines in the most beautiful nuances from red to shocking pink. Rubelite is rich in lithium and free of magnesium and iron. Color: Hot Pink to Intense red Categories: semi-precious stone Chemical Composition: (NaCa)(LI,MgFe,Al)9B3Si6(O,OH)31 Crystal Group: Hexagonal Refractive Index: 1.624(+.005, -.005) - 1.644(+.006, -.006) Hardness: 7-7.5 Density: 3.06 (.05, +.15) Occurrence: Brazil, Madagascar, Nigeria, U.S.A.
| Natural Sapphirine Sapphirine is a rare mineral, a silicate of magnesium and aluminium.Though Sapphirine clearly falls into the "rare stone" category, it is a relatively durable stone with a Moh's hardness of 7.5. Sapphirine's very distinctive appearance along with their somewhat unusual durability have made them fairly popular with collectors. Color: Pale blue, bluish gray, greenish gray, green, purplish pink Categories: semi-precious stone Crystal Group: Monoclinic Refractive Index: 1.714-1.723 Hardness: 7.5 Density: 3.4-3.5 Occurrence: U.S.A., U.K., Sweden, Czechoslovakia, Japan, South Africa, Greenland, Madagascar, Italy, Sri Lanka
|
|