tanzanite (4)

Description

Origin : Tanzania (Morongoro)

Size : 4.5k - mm 12 x 11 x 5

natural crystal tanzanite, 4.5 carats, mm 12 x 11 x 5, as in picture.
Also available in lots and worked gems, at this link, as well as Rubyzoisite.

Tanzanite is a variety of Zoisite; it was discovered in early January 1967 in northern Tanzania at the foot of the Merelani mountains near the city of Arusha. Its most common use is in jewellery: appreciated thanks to its crystalline characteristics and pleochroism (the color that goes from blue to violet, changing according to the orientation of the light and which is precisely defined as bluviola).
Tanzanite is a rare gem. The name Tanzanite was given to it by the Tiffany maison in honor of the state in which the gem was discovered. Before the final name, the hypothesis of giving it the commercial name of blue Zoisite was rejected because it sounded too similar to the English term suicide (suicide). Many names were also proposed such as sapphire from Mount Meru, zoisite-sapphire and sapphire-zoisite. At the time the title of discoverer of Tanzanite was attributed to a certain Manuel D'Souza but it was later ascertained that the real discoverer was an inhabitant of the place named Ndugu Jumanne Ngoma, who, after numerous vicissitudes, managed to obtain recognition, endorsed in 1984 by a certification from the Ministry of Mineral Resources of Tanzania.
The largest deposit is located in Tanzania (Africa) in the Arusha region and has an area of 20 km². However, it is not the only one existing, in fact also in Pakistan (Asia) the extraction of tanzanite takes place, however not all the crystals extracted in Asia can be marketed.