A 29.6 carat blue diamond, one of the rarest and most coveted in the world with a possible price tag of tens of millions of dollars, has been discovered at a South African mine by Petra Diamonds.
The miner said the "exceptional" acorn-sized diamond, small enough to fit into the palm of a hand, was unearthed at the Cullinan mine near Pretoria.
The mine, owned by the firm since 2008, was also where the Cullinan Diamond was found in 1905—described as the largest rough gem diamond ever recovered and weighing 3,106 carats.
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Other notable diamonds found in the mine include a 25.5 carat Cullinan blue diamond, found in 2013 and sold for $16.9 million, and a diamond found in 2008, known as the Star of Josephine, which was sold for $9.49 million.
Source: Petra Diamonds
Chief Executive Johan Dippenaar told Reuters the latest blue diamond discovery could outstrip recent finds.
"By some margin … this is probably the most significant stone we've ever, in terms of blue stones, recovered," he said.
"The stones in the last year or so are selling well above $2 million per carat. That's not my quote, that's updates in the market," he said ahead of the company's first-half trading statement.