What is Tanzanite?

Tanzanite is a gem in the Zoisite mineral group. It is found in Tanzania (hence the name). The colour is ultramarine to sapphire blue. In its natural state, it has yellow and brown tinges. These are usually removed by heat treatment so the basic violet blue hue is intensified.


The mineral Zoisite was first found in Austria in 1805. Tanzanite was first identified in 1962 near Mount Kilimanjaro and mining commenced in 1967. Tiffany and Co. introduced Tanzanite to the US market in 1970.


It is believed that the stone has the power to improve sight and that it is beneficial to the skin.


Tanzanite is somewhat brittle and must be handled carefully. Do not store with other gems or hard objects. It cannot be cleaned in an ultrasonic device or in a steamer. Avoid banging it as Tanzanite can break.

 Wash in warm, sudsy water and dry with a soft cloth.


Caring for Tanzanite (Summary)

  • Wash in warm, soapy water
  • Handle carefully
  • Avoid acids.


Tanzanite measures 6.5 on the Moh’s hardness scale. The crystal system is Orthorhombic. The density is 3.35.

It is composed of calcium, aluminium hydroxsysilicate.