Gem and mineral hardness is measured on the Mohs scale, with Diamond being the hardest mineral (10) and Talc being the softest (1). Tanzanite sits at between 6 and 7 on the scale - a similar hardness to Garnet and Moonstone.

Tanzanite is not a gem that should break easily but it can scratch more easily than harder coloured gems like Ruby and Sapphire.

Due to Tanzanite's relative softness, it should be treated with respect. It is generally advised that you should not wear coloured gemstones while doing heavy or rough work (such as cleaning, gardening or performing sports activities) avoid contact with gritty substances and remove whilst swimming due to the chlorine in pools.

Gems with a hardness of 6-7 or greater are quite suitable for rings which are worn occasionally. But for a ring like a wedding or engagement ring, intended for everyday wear over a period of years, a hardness rating of 8-10 (for example Ruby, Sapphire, Spinel, Topaz, Cat’s Eye, Alexandrite or Diamond) is recommended.

When worn, pendants are much more protected than rings, so Tanzanites are fine to wear every day as a pendent. I’d still recommend removing them before sports or swimming, or showering.

On a personal note, I’ve worn Tanzanite jewellery out on many occasions, but treat it more like event/cocktail jewellery. In the Tanzanite Trillion rings I’ve designed, the claws are a little larger to protect the corners of the triangle, and the halo of diamonds surrounding the main stone, also helps to protect the Tanzanite.

To clean Tanzanite, never use an ultrasonic cleaner or steam cleaner (often found in jewellers). The best method is simply to use a toothbrush and warm, soapy water.

Looking to buy Tanzanite Jewellery? Check these out: