Nearly all tanzanite has been heat treated to produce the striking violet-blue colour, with the natural colour being a petrol or yellow-brown.
With only one economic deposit currently in production, Tanzanite is a member of the gemstone endangered species list. Estimates vary, but in all likelihood with consumption continuing at its current levels, it is believed the Merelani Hills deposits of Tanzania will be completely depleted within 20 years.
Tanzanite, while a beautiful stone, has a low hardness compared to other gemstones and should be worn with care in all but designs that prevent the gem from being knocked or scratched.
Tanzanite (and Blue Topaz) is the birthstone for December.
