Johannesburg - Lucara Diamond Corporation completed the first stage of upgrading its processing plant at the Karowe mine in Botswana that would introduce technology to recover some of the world’s biggest diamonds.
The upgrades will allow the company to sift diamonds as big as 90mm amid tons of mining rubble, the Vancouver-based company said in a statement on Tuesday.
Last year, Lucara recovered a 1 109-carat gem at Karowe, which was the world’s second-largest diamond even after breaking off a 374-carat chunk in the process.
Two African mines, Lucara’s Karowe and Gem Diamonds’ Letseng in Lesotho, consistently produce diamonds that rank among the biggest. It presents a challenge to miners, who have to crush vast amounts of waste rock to find the gems.
Lucara and Gem are investing in bigger, costlier filters and laser diamond identification technology to find the large stones before crushing the ore.
Lucara’s new technology “would allow for the recovery of a diamond of similar size to the 3 106-carat Cullinan diamond recovered in 1905”, it said.
The Cullinan, retrieved with a pocket knife from the wall of a mine in South Africa, is the biggest diamond ever found and now makes up part of the British crown jewels.
Lucara is also holding a sale of 12 diamonds with a combined weight of 1 100 carats from November 7 to November 14, according to the statement today.
BLOOMBERG