Shares in Gem Diamonds sparkled today as the firm said it had uncovered the fifth-largest gem-quality diamond ever found.
The firm announced the discovery of an "exceptional quality" 910 carat diamond from its Letseng mine in Lesotho - a mine in southern Africa renowned for producing large diamonds. The diamond is the largest ever recovered from Letseng, which Gem Diamonds acquired in 2006.
SP Angel's John Meyer said the stone was approximately the size of two golf balls and was classified as a D colour Type IIa diamond, meaning it has almost no impurities and is therefore one of the most expensive discoveries.
The news sent the company's share price up as much as 15 per cent this morning. At the time of writing, its shares were up 14.22 per cent at 92.06p.
Famous Type IIa diamonds include the Cullinan (which was cut into 105 diamonds, including several for the British Crown Jewels), Koh-i-Noor and Lesedi la Rona.
"This exceptional top quality diamond is the largest to be mined to date and highlights the unsurpassed quality of the Letseng mine. This is a landmark recovery for all of Gem Diamonds' stakeholders, including our employees, shareholders and the government of Lesotho, our partner in the Letseng mine," said Clifford Elphick, Gem Diamonds' chief executive.
Gem Diamonds owns 70 per cent of the Letseng mine and the government of Lesotho owns 30 per cent.
Gem Diamonds has not yet commented on its plans to sell the diamond.
Lucara Diamond's 813-carat Constellation rough diamond sold for $63m (£46m) in 2016 while its Lesedi La Rona, which weighed a record-breaking 1,109 carats was sold to jeweller Laurence Graff for $53m in September.
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