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Rocks & Minerals Co

Tanzanite

Tanzanite is the blue/purple variety of the mineral zoisite (a calcium aluminium hydroxy silicate) discovered

in the Mererani ills of Manyara Re!ion in "orthern Tanzania in #$%' near the city of rusha and Mount

iliman*aro+ ,t is used as a !emstone+ Tanzanite is noted for its remarkably stron! trichroism' appearin!

alternately sapphire blue' violet and bur!undy dependin! on crystal orientation+

Tanzanite can also appear differently -hen vie-ed under alternate li!htin! conditions+ The blues appear

more evident -hen sub*ected to fluorescent li!ht and the violet hues can be seen readily -hen vie-ed under

incandescent illumination+ Tanzanite in its rou!h state is usually a reddish bro-n color+ ,t re.uires artificial

heat treatment to % 0C in a !emolo!ical oven to brin! out the blue violet of the stone+ Tanzanite is a rare

!em+ ,t is found only in the foothills of Mount iliman*aro+ The mineral -as named by Tiffany & Co+ after

Tanzania' the country in -hich it -as discovered+ 1ecause it is relatively soft' tanzanite is most commonly set

in necklaces and earrin!s+

2ource3 -ikipedia' the mineralo!ist