A flawless 100-carat diamond ring has sold for £14.8 million at auction in New York.
The perfect classic emerald-cut D color diamond, which is about the size of a walnut, was mined by De Beers in southern Africa.
It was purchased for $22.1m (£14.8m), which includes the buyer's premium, by an anonymous buyer via a telephone bid at an auction at Sotherby's.
The gem had a pre-sale estimate of $19m to $25m.
Gary Schuler, head of Sotheby's jewellery department in New York, described the diamond as "the definition of perfection".
He said: "The color is whiter than white, it is free of any internal perfections, and so transparent that I can only compare it to a pool of water."
The gem was the highlight of a sale of more than 350 jewels expected to sell for a total of more than $50m.
Only six perfect diamonds weighing more than 100 carats have been sold at auction in the last 25 years.
In 2013, a 118.28 carat white diamond sold for a record price of $30.6 million in Hong Kong.
Two years ago, a flawless pink diamond known as the Pink Star set a world record price for a gemstone at auction when it sold for $83m in Geneva.