Gemstone Focus: Tanzanite


Tanzanite is the new kid on the block. It was officially recognised as a birthstone of December in 2019, replacing Blue Topaz which has been moved to join its cousins as the November birthstone.

Tanzanite was first identified in Tanzania in 1962, but was originally not highly valued In 1967 the primary deposit was identified.Its primary use was a an inexpensive substitute for Sapphire. However, in 1968, Tiffany & Co. recognised it might have mass appeal and began to promote it massively as Tanzanite and since then it has gone from strength to strength owing to it’s stunning blue/purple colour.

Tanzanite is now also the gemstone for the 24th anniversary.

Facts, Care and Value

Tanzanite is the blue / purple variety of zoisite, currently it is mined in only one place, the Merelani Hills of Tanzania. Most all Tanzanite is heat treated to achieve the lovely colour as most mined tanzanite is grey. Occasionally purple crystals are found on the ground or near te surface. The colour in these cystals is usually the result of exposure to sun heating. Hence heat treatment is accepted as standard.

Tanzanite is a relativey soft stone and can be prone to cracking or chipping. Sitting at 6.6 n the Mohs scale, it can be easily scratched by household dust. Thus this beautiful gemstone is best suited for occasional wear in rings and other jewelley subject to knocks and abbrasions. It is most suited to earrings and pendants for daily wear. And can benefit from more protective settings

In terms of value, finding good quality tanzanite in smaller stones is not easy. And prices rise exponentially. They tend to have good clarity, though you can occasionally find some with a very rare cat’s eye effect. In general you can find faceted stone ranging from $75 – $500 per carat depending mostly on colour and clarity. Stones in the blue to violet range are most desired. Lower grade tanzanite is usually turned into beads.

Thanks for reading!

Leave a Reply

Your email address will not be published. Required fields are marked *