Saturday, 31 December 2016

Tanzanite

Tanzanite is the blue/purple variety of the mineral zoisite. It was discovered in the Mererani Hills of Manyara Region in Northern Tanzania in 1967, near the city of Arusha and Mount Kilimanjaro.

Naturally formed tanzanite is extremely rare. Tanzanite is noted for its remarkably strong trichroism, appearing alternately sapphire blue, violet and burgundy depending on crystal orientation.
Tanzanite is a relatively new gemstone in the world of gemology and jewelry. Since its discovery, tanzanite has sold for as little as $20 per carat and as much as $1,000 per carat or more, for gem-quality, finely coloured stones.
That price may seem like a bargain in time, as tanzanite is a one-source gemstone and that source is expected to be mined out within the next 15 to 25 years.
Pleochroic means tanzanite offers three distinct colors in three crystal directions. Tanzanite has a Mohs hardness of 6 to 7.