Gemology: T is for ...

We're nearing the end of our Gemology guide now, but we still have a few gems to bring you. In our guide to Gemstones Beginning with T we think you'll discover a couple of rare and unusual beauties that you've probably never heard of before! In gemology, T is for ...


If you've heard of Taaffeite before, well done you! This gemstone, believe it or not, was discovered AFTER it had been cut and polished and put on display in an Irish jeweller's store! All Taaffeite prior to this had been misidentified as spinel, until mineralogist Richard Taaffe purchased the polished gem in 1945 and noticed a few inconsistencies. He sent the gem away for chemical testing and it was found to be something completely new and given his name. Taaffeite is very rare with small deposits being found in Sri Lanka and Tanzania alongside other gemstone minerals. Found in translucent watery pink/purple, it's definitely a stone for the connoisseur!

Cut and Polished Taaffeite samples

Image Attribution: By DonGuennie (G-Empire The World Of Gems) [CC BY-SA 4.0 (], from Wikimedia Commons


This is a rare gemstone discovered in 1967 and found only in a six kilometer strip of land near Mount Kilimanjaro in Tanzania. When mined it's a yellowish-brown colour, but when seen in jewellery it's a rich purpley-blue. This is because the gemstones are heat-treated to around 450º celcius which causes the colour change. It's quite a fragile gem, being soft and easily broken, so it's often more of a collectors' piece for avid fans of rare gems.

Tanzanite Gemstone Pendant