Natural coloured diamonds are rare, and finding vivid and intense blue, pink and yellow diamonds is always a cause for mining companies to celebrate.

Finding a violet diamond though? It’s almost unheard of in the diamond industry.

Yet, that’s what Rio Tinto found last year in their Argyle mine, located in Western Australia. Described as “impossibly rare”, this remarkable piece of 9.17ct rough diamond took Argyle master cutter Richard How Kim Kam 80 hours of polishing, ultimately revealing a remarkable 2.83ct violet diamond.

Graded by the Gemological Institute of America (GIA) as a Fancy, Deep Grayish Bluish Violet colour, the Argyle Violet will form the centerpiece of the 2016 Argyle Pink Diamonds tender, where it is expected to sell for more than US$2.9million.

Argyle produces more than 90% of the world’s pink diamonds and, according to mine owners Rio Tinto, is the only source of hydrogen-rich violet diamonds in the world.

But, how rare is “impossibly rare”?

In 32 years of mining at Argyle, only 12 carats of polished violet diamonds have been produced. Josephine Johnson, Argyle Pink Diamonds manager, said, “We are very excited to announce this historic diamond ahead of our Tender launch. This stunning violet diamond will capture the imagination of the world’s leading collectors and connoisseurs.”

Since opening in 1983, Argyle mine has produced over 800 million carats of rough diamonds and is one of the world’s largest suppliers of natural coloured diamonds.

The 2016 Argyle Pink Diamonds Tender will commence private trade viewings in June and travel to Copenhagen, Hong Kong and New York.

Images: Rio Tinto