Tanzanite
Tanzanite belongs to the mineral species zoisite. The name was given by Abraham Werner in 1805 after Baron von Zois, who first found the mineral zoisite in the Alps. Green and brown zoisites should be traded as “green and brown zoisites”, not “green tanzanites”.
Tanzanite, Tanzania (22.85 ct)
Class: Silicates
Genesis: Metamorph
Colours: blue-violet, blue, violet
Hardness: 8 (Due to its good cleavage, this stone is difficult to cut.)
Main deposits: Tanzania
Tanzanite is named after the found land of Tanzania, where it was found in 1967 in the Merelani Mountains in the Lelatema District and this area is the only mining area to date.
The color can be changed from brown-blue to blue by heating, which is what nature has done in many cases with tanzanites, which occur at excavation depths of less than 700 meters. Unfortunately, explosive material has to be used at such depths, which is critical for the acquisition of larger rough stones in the case of the easily fissile tanzanite. Tanzanite is colored blue by the element vanadium, interestingly vanadium is the cause of green, not blue, in many other minerals. Tanzanite is one of the most difficult gemstones to cut.
