Rock of ages: Huge 1,111-carat diamond is biggest found in more than a century

A 1,111 carat gem-quality diamond, second in size only to the Cullinan diamond cut into the British Crown jewels, has been unearthed by Lucara Diamond Corp in Botswana.

The Type-IIa stone, just smaller than a tennis ball, is the largest diamond found for more than 100 years, according to Vancouver-based Lucara. It was recovered by machines at the south lobe of Karowe mine in central Botswana, the company said in a statement.

“We’ve always thought very highly of our resource,” William Lamb, chief executive officer of Lucara, said on a call with investors Thursday. “You’d have to be a very brave person to predict a stone like this.”

Lucara’s Karowe mine in Botswana is rivaling Gem Diamonds Ltd’s Letseng operation in Lesotho as a source of the world’s biggest and best stones. Gem Diamonds previously held the record for the largest discovered this century with the 603-carat Lesotho Promise.

“It is almost impossible to estimate a value for such an extraordinary stone given that a valuation is highly dependent on the colour, clarity and cutting and polishing characteristics,” Edward Sterck, a London-based analyst at BMO Capital Markets, wrote in a note Thursday.

Lucara sold a 341.9-carat Type-IIa diamond in July for US$20.6 million, or US$60,000 a carat, Sterck said. The company’s shares jumped as much as 37 per cent in Toronto trading, the steepest intraday gain since 2008.