An anonymous buyer purchased the perfect classic emerald-cut diamond, which is about the size of a walnut and was discovered by De Beers in one of its mines in South Africa, via a telephone bid on Tuesday.
The diamond had a pre-sale estimate of $19-million to $25-million.
Gary Schuler, the head of Sotheby’s jewellery department in New York, said the gem was the definition of perfection.
“The colour is whiter than white, it is free of any internal imperfections and so transparent that I can only compare it to a pool of water,” he explained.
The $22.1-million price tag, which includes the buyer’s premium, fell short of the $30.6-million world record price paid for a 118.28 carat white diamond in Hong Kong in 2013. Sotheby’s said only six perfect diamonds weighing more than 100 carats have sold at auction in the past 25 years.
A flawless pink diamond, dubbed the Pink Star, set a world record price for a gemstone at auction when it sold for $83.02-million in Geneva in 2013.
Schuler said the distinguishing characteristic of the huge diamond sold on Tuesday was its size and beautiful shape. Originally weighing more than 200 carats, its owner spent more than a year perfecting its cut and polish.
Sotheby’s said the price per carat for a 100-carat perfect diamond had risen from $125 000 to $260 000 between 1990 and 2013. – Reuters