Rio Tinto discovers rare white diamond at Argyle

Image: Rio Tinto

Rio Tinto has revealed one of the largest gem-quality white diamonds in the 35-year history of its Argyle mine in the Kimberley, Western Australia.

The diamond, which was found at the mine last month, weighs 28.84 carats and will be sold in Antwerp, Belgium later this year.

Dubbed Argyle Octavia, due to its octahedral shape, the reveal comes six months after the mine unveiled its largest ever Fancy Purplish Red diamond, the 2.28-carat Argyle Muse.

Such finds are exceedingly rare at Argyle, which is better known for its coloured diamonds, particularly pink and purple varieties. The company did not give a price estimate for Argyle Octavia, but due to its shape, size and rarity it can safely be expected to command a large value at auction.

“We are delighted with this discovery which is a testament to the extraordinary Argyle orebody that continues to deliver these miracles of nature, even as it nears the end of mine life,” Rio Tinto Copper and Diamonds chief executive Arnaud Soirat said.

Since launching operations in 1983, the mine’s output of gem quality white diamonds weighing more than 20 carats has amounted to the equivalent of fewer than one in every 14,000 gems, or “0.00007 per cent of Argyle’s production”, according to the company.

“Argyle Octavia is unique in its size, shape and beautiful provenance and will take its place in Argyle’s history as one of a few special large white diamonds ever to be produced from the mine,” Argyle general manager Andrew Wilson said.

Rio Tinto is expected to close the Argyle mine next year.

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