Petra Diamonds finds rare 25.5 carat blue gem

Petra blue diamond

Rough 25.5 carat stone

Petra Diamonds (LSE:PDL) announced it recovered a 25.5 carat blue diamond at the Cullinan mine in South Africa.

The gem is considered to be of high quality and top colour. Blue diamonds are rare and the most highly coveted.

Previously, the company extracted a similar 26.6 carat rough stone which was polished into a flawless fancy vivid blue 7 carat diamond, which sold at auction for $9.49 million in 2009 and then named the Star of Josephine.

Petra Diamonds has interests in eight producing mines: seven in South Africa and one in Tanzania.

The Cullinan mine has produced many of the world's largest diamonds.

Image courtesy Petra Diamonds