Stone Information & Mining
Tanzanite is the blue to violet to purple variety of the mineral zoisite. It is mined commercially only in one area of the world: the Merelani Hills of Tanzania, which is where it gets its name. Tanzanite’s appearance is influenced greatly by its pleochroism, which is the ability of a gemstone to show different colors when viewed in different crystal directions. Tanzanite can be violetish blue—similar to a sapphire color—or much more purplish. Often, both the violetish blue and purplish colors are readily visible in a fashioned stone when it is gently rocked and tilted. Tanzanite is relatively new to the colored stone galaxy.
Legend & Lore
As the most common story of the tanzanite mining boom goes, in 1967 a Masai tribesman stumbled upon a cluster of highly transparent, intense 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. Tiffany & Company recognized its potential as an international seller and made a deal to become its main distributor. Tiffany named the gem after the country it came from, and promoted it with a big publicity campaign in 1968. Almost overnight, tanzanite was popular with leading jewelry designers and other gem professionals, as well as with customers who had an eye for beautiful and unusual gems. The instant popularity of this transparent blue to violet to purple gem was tied to its vivid color, high clarity, and potential for large cut stones.
Tanzanite can be violetish blue—similar to a sapphire color—or much more purplish. Often, both the violetish blue and purplish colors are readily visible in a fashioned stone when it is gently rocked and tilted.
Warm, soapy water is always safe. Ultrasonic and steam cleaners are never recommended for tanzanite.
This information was excerpted from GIA's Gem Encyclopedia with permission from GIA.