Tanzanite - Arusha, Merelani Mountains, Tanzania
 
 This 2.2 cm x 1.4 cm tanzanite crystal shows all the properties of this rare zoisite variety. The wide crystal has a flawless transparency and apart from a few stress cracks it is of the best gemstone quality. 
 The characteristic trichroism, which moves in the play of colors between blue and purple, is very well pronounced in this untreated piece.