Tanzanite

The name tanzanite was a trade name coined by Tiffany & Co. shortly after the gem's were discovered, an obvious allusion to its country of origin. This was thought necessary in order to make the stone remarkable to the public: the name has since stuck as a varietals designation. Tanzanite's present-day popularity as a gemstone is very largely thanks to Tiffany's marketing campaigns. The mining of tanzanite nets the Tanzanian government approximately USD $15 million annually, the finished gems later being sold mostly on the US market for its sales totaling approximately USD $400 million annually.

History

The gemstone discoveries in East Africa in the 1950s transformed the jewelry world: new varieties, new colors, and also new variations on existing species made that decade the most exciting time in its gemstone industry in our lifetimes.

But no gemstone discovered in East Africa had more of an impact on the world gemstone market than tanzanite, a velvety blue variety of the mineral zoisite that was found during the first time in 1966 and named after the country of its birth by Tiffany & Co in New York, who actually introduced the gemstone to the world market in 1968.

Tanzanite is the blue/purple variety of the mineral zestier (Ca2 (Aloha) Al2 (SiO4)3) discovered in the Meralani Hills of northern Tanzania in 1968, near the city of Arusha. It was a popular and valuable gemstone when it is cut, although its durability is somewhat lacking; its tendency to break precludes appropriate use as its ring stone. Tanzanite is noted for its remarkably strong trichroism, appearing alternately sapphire blue, violet, and also sage-green depending on crystal orientation. However, most tanzanite is subjected to artificial heat treatment to improve its colour: this significantly subdues its trichroism.

Colour and Value

Tanzanite is the ultimate prize of a gem safari. Its rich purples and also blues often have a depth comparable to the finest sapphire. Paler tanzanite had a delicate periwinkle color like the eyes of Elizabeth Taylor. It is supremely rare, coming from only one place in the world, the Merelani Hills of Tanzania, in the shadow of Mount Kilimanjaro.

New mining techniques and its liberalization of the Tanzanian economy has helped to boost production in the past few years to make tanzanite more available than ever in the history of the gemstone.

The source of its mesmerizing color is that tanzanite is actually trichroic: that is, it shows different colors when viewed in different directions. One direction is blue, another purple, and another bronze, adding subtle depths to its color. When tanzanite is found in the ground, the bronze color dominates. However, with gentle heating, the cutter could watch the blue color bloom and deepen in the stone.