Recently, Sotheby’s set a new global diamond auction record in Hong Kong: a blue colored diamond from diamond miner and retailer De Beers De Beers sold for us $57.5 million (or HK $451 million, about 380 million yuan). This blue diamond weighs 15.1 carats, which is extremely rare. It is also the largest blue color diamond in the history of auction. The world’s largest flawless blue diamond auctioned in Hong Kong with a transaction price of 400 million De Beers said that such a heavyweight blue diamond is extremely rare. Only five blue diamonds of more than 10 carats have appeared in the auction history, and none of them exceed 15 carats. This flawless blue diamond itself is a milestone. “De Beers blue” is not only the largest brilliant blue diamond at the auction in history, but also the largest flawless cutting brilliant blue diamond identified by GIA in history. “This diamond is one of the best in De Beers’ history,” De Beers Group CEO Bruce cleaver said in a statement, describing the diamond as “extremely rare and unique.” “De Beers blue” is derived from a blue diamond original stone found in Cullinan mine, South Africa, in April 2021. GIA American Gem Institute rated the blue diamond as “brilliant color grade”, while in the rating agency, only 1% of the blue diamond belongs to this grade, which is very rare. According to the identification of the American Gem Institute, the blue diamond is “flawless inside” and has excellent grinding. It belongs to type IIB. The diamond with such texture is less than 0.5% in the world. This is why the “Haoyu blue” blue diamond is considered to have high collection value.