Petra Diamonds sells rare blue gem for $16.9m

Petra Diamonds (LSE:PDL) sold its 25.5 carat blue diamond for $16.9 million on Friday.

The rare high quality coloured gem was extracted in April from the Cullinan mine in South Africa.

The company said the bidding was highly competitive.

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

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

Related: Petra Diamonds finds rare 25.5 carat blue gem

Image courtesy Petra Diamonds