Petra Diamonds has announced that it will put a rare blue, cushion-shaped diamond weighing 7.03ct up for auction at the upcoming Sotheby’s Magnificent Jewels sale in Geneva. The pre-sale estimate for the stone is $5.8m to $8.5m (£4.1m to £5.9m) and the buyer will select a name for the diamond.

Discovered in Petra Diamonds’ Cullinan diamond mine in South Africa, the diamond was cut from a 26.58ct rough stone. Petra Diamonds said that the stone ranks amongst the most important blue diamonds ever to be offered for sale at Sotheby’s. It has received the highest possible grading from The Gemological Institute of America, which marked it as a fancy vivid blue colour and internally flawless in clarity.

Petra Diamonds chief executive John Dippenaar said: “This fancy vivid blue, flawless diamond is a very rare and unique gem. Its quality is enhanced by its Cullinan origins, a mine that has produced some of the world’s most famous diamonds. Given its distinguished heritage, it is fitting that Sotheby’s should further establish its legacy by marketing the gem as the cornerstone of its exclusive Magnificent Jewels collection in Geneva.”

Sotheby’s Magnificent Jewels sale will be held at the Beau-Rivage Hotel in Geneva on May 12.


Related stories
Production and revenue rocket at Petra Diamonds
Profitable full-year results for De Beers
Special sales revive cooldiamonds.com
Idex Online improves online diamonds trading site