According to the company, the 910-carat, D-colour, type IIa diamond – which was colourless with no visible impurities – was the largest find from its Lesotho, Africa mine.
Gem Diamonds CEO Clifford Elphick described the discovery as a “landmark recovery”.
“Since Gem Diamonds acquired Letšeng in 2006, the mine has produced some of the world’s most remarkable diamonds,” Elphick said.
“This exceptional top quality diamond is the largest to be mined to date and highlights the unsurpassed quality of the Letšeng mine,” he added.
According to reports, the diamond is expected to fetch up to US$40 million (AU$49.6 m).
Before the remarkable find, the largest discovery from the Letšeng mine was a 603-carat diamond dubbed the Lesotho Promise. It was subsequently auctioned in 2006 for US$12.4 million (US$AU15.3 m).
It was later auctioned off in 2006 for US$12.4 million (US$AU15.3 m).
However, the largest diamond ever discovered is still the 3,106-carat Cullinan diamond found in South Africa in 1905.
To date, Gem Diamonds has found two D-colour stones from the mine that weighed 117 and 110 carats. In 2017, the company recovered seven diamonds weighing 100 carats or more.
Gem Diamonds owns 70 per cent of the Letšeng mine, with the remaining 30 per cent controlled by the government. The mining company also owns the Ghaghoo mine in Botswana.
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