London, England — 19 April 2013 – Leading independent diamond mining group Petra Diamonds Limited has announced the recovery of a 25.5 carat blue diamond at the Cullinan mine in South Africa. The stone is considered to be a high quality gem diamond of top colour.
Blue diamonds are among the rarest and most highly coveted of all diamonds, and the Cullinan mine is the most important source of blues in the world.
Since Petra acquired the mine, it has produced a number of blue diamonds, including a 26.6 carat rough stone which yielded a fancy vivid blue and internally flawless 7.0 carat polished stone. This important and rare diamond sold for US$9.49 million (or US$1.35 million per carat) at a Sotheby’s auction in May 2009.
At the time this was the highest price per carat for any gemstone sold at auction, and the highest price for a fancy vivid blue diamond sold at auction. It was subsequently named the ‘Star of Josephine’ by its new owner.
Many of the world’s most magnificent gems have been recovered at Cullinan, including the world’s largest gem diamond on record “’ the Cullinan at 3,106 carats rough “’ as well as the two largest polished diamonds in the world “’ the Golden Jubilee (545 carats) and the Great Star of Africa (530 carats).
Cullinan is renowned as a source of large diamonds and frequently yields diamonds larger than 10 carats. Furthermore, it has produced over 750 stones weighing more than 100 carats, 130 stones weighing more than 200 carats, and around a quarter of all diamonds weighing more than 400 carats.
Source: Petra Diamonds. For more information, click here.