Photo of Tanzanite in Processed & Rough Form
Tanzanite is a mineral with a hardness of 6 out of 10 on the Mohs scale of mineral hardness [?]. These Orthorhombicly structured gems are made of calcium aluminum silicate hydroxide, their full chemical compound being Ca2Al3(SiO4)(Si2O7)O(OH).
Tanzanite is something of bluish to violet variety of zoisite, that wasnt discovered until 1967 believe it or not. It was first found in the Mererani Hills of northern Tanzania. Tanzanite has strong trichroism, appearing alternately blue, violet, or burgundy depending on the crystal orientation and lighting conditions.
Most tanzanite is heat-treated to enhance the color, and natural tanzanite seems to contain more brownish pigments that are not really associated with a quality stone.
The specific gravity [?] for Tanzanite is 3.35, its refractive index [?] is 1.69-1.70, and its double refraction [?] is 0.009.
History
Tanzanite was named after Tanzania, the country where it was found, that statement might be self explanatory. Tiffany and Co first introduced it to the market in 1968, promoting it as an exotic gemstone. In recent years tanzanite has gained immense popularity and was added as an alternative December birthstone by the American Gem Trade Association in 2002.
Industrial Usages
Tanzanite is currently too rare to have any known industrial applications.
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