Description

The instant popularity of this transparent blue-to-violet gem. Tanzanite is only found in Tanzania, in a very small mining area near the Mirerani Hills. Tanzanite is the blue and violet variety of the mineral zoisite (calcium aluminium hydroxyl sorosilicate), caused by small amounts of vanadium.

Tanzanite is noted for its remarkably strong trichroism, appearing alternately blue, violet and burgundy depending on crystal orientation. Tanzanite can also appear differently when viewed under different lighting conditions. The blues appear more evident when subjected to fluorescent light and the violet hues can be seen readily when viewed under incandescent illumination. In its rough state tanzanite is colored a reddish brown to clear, and it requires heat treatment to remove the brownish "veil" and bring out the blue violet of the stone. Tanzanite is relatively new to the colored stone galaxy. As the most common story of the tanzanite mining boom goes, in 1967 a Masai tribesman stumbled upon a cluster of highly transparent, intense violet-to-blue crystals weathering out of the earth in Merelani, an area of northern Tanzania. He alerted a local fortune hunter named Manuel d'Souza, who quickly registered four mining claims.

D’Souza hoped that he’d been shown a new sapphire deposit. Instead, the deposit contained one of the newest of the world’s gems.