Most expensive diamond sold at auction

How it was set

The Pink Star sold at Sotheby's Magnificent Jewels and Jadeite sale in Hong Kong on 4 April 2017. Chow Tai Fook bought the stone for about $71.2 million after edging out two other bidders. The winning bid came over the phone from the company's chairman. Sotheby's experts had expected a price above $60 million. De Beers mined the rough stone in 1999, when it weighed 132.5 carats. Cutting and polishing took about two years.

About the Pink Star

The Pink Star is an oval diamond weighing 59.60 carats (11.92 grams). The Gemological Institute of America rates its color Fancy Vivid Pink, and it is the largest known diamond with that rating. The stone was unveiled in Monaco in 2003 and was later shown in the Smithsonian's diamond exhibit. It is one of the few diamonds of its size and color ever offered at auction, which is why its price drew so much attention.

The record before this one

The previous record was about $57.5 million for the 14.62-carat Oppenheimer Blue, sold at Christie's in Geneva the previous May. The Pink Star also had an earlier sale at Sotheby's in Geneva in November 2013, for about $83 million. That sale was never completed because the buyer defaulted in February 2014, and the auction house took the stone back. Sotheby's said the 2017 price was more than double the earlier record for a fancy vivid pink diamond.