The biggest gem-quality rough diamond found in more than a century has been sold to jeweller Laurence Graff for $53m (£39m).
The Lesedi La Rona, the world's most valuable rough diamond, weighs a record-breaking 1,109 carats and is about the size of a tennis ball.
It was unearthed by Canadian miner Lucara Diamond Corp nearly two years ago at its Karowe mine in Botswana.
Graff, chairman of Graff Diamonds, said he was "thrilled and honoured" to buy the diamond, which he called a "remarkable gift from Mother Nature".
The British diamond magnate bought the stone for $47,777 per carat and will now cut and polish it.
William Lamb, president and chief executive at Lucara, called the discovery of the diamond a "company-defining event", and he added that the sale was an improvement on the highest bid received at a Sotheby's auction in June 2016.
The diamond was second in size to the more than 3,000-carat Cullinan stone which was cut into 105 diamonds, including several for the British Crown Jewels.
Despite its high standing, the diamond sold for less than the cut Pink Star diamond this year, which fetched a record-breaking $71.2m, and less than the 813-carat Constellation rough diamond, which was said to have a better colour and sold for $63m under the hammer in 2016.
BMO Capital Markets had forecast the diamond could sell for $75m at the Sotheby's auction last year.
Shares in Canada-listed Lucara jumped 6.96 per cent to $2.46 at the time of writing.