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Tanzanite is the blue and violet variety of the mineral zoisite (a calcium aluminium hydroxyl sorosilicate), caused by small amounts of vanadium. [3] Tanzanite belongs to the epidote mineral group. Tanzanite is only found in Simanjiro District of Manyara Region in Tanzania , in a very small mining area approximately 7 km (4.3 mi) long and 2 km ...
International Gemological Institute (IGI) is a gemological organization which certifies diamond, colored stone and jewelry. It was established in 1975 in Belgium. It was established in 1975 in Belgium.
International mining companies dominate the industry in the extraction of gold and diamonds, with additional small scale mining operations scattered across the country. [ 2 ] Tanzania is the fourth-largest gold miner in Africa behind South Africa , Mali , and Ghana , [ 4 ] and in 2010 accounted for 2% of the world's gold output. [ 7 ]
Zoisite may be blue to violet, green, brown, pink, yellow, gray, or colorless. Blue crystals are known under the name tanzanite. It has a vitreous luster and a conchoidal to uneven fracture. When euhedral, zoisite crystals are striated parallel to the principal axis (c-axis). Also parallel to the principal axis is one direction of perfect cleavage.
The tanzanite resource is a long narrow area, divided into four blocks: named " A" to "D". TanzaniteOne Mining own the licence to mine the largest area Block C. Medium scale mining is undertaken by Kilimanjaro Mining in Block A and Tanzanite Africa in Block D-extension.
They also replaced December's lapis with zircon and switched the primary/alternative gems for March. The American Gem Trade Association added tanzanite as a December birthstone in 2002. [5] In 2016, the American Gem Trade Association and Jewelers of America added spinel as an additional birthstone for August. [6]
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