'Outstanding' and Rare 29.6-Carat Blue Diamond Found in South Africa Could Cost Tens of Millions of Dollars

A rare blue diamond was discovered in a mine in South Africa which could cost fortunes.

The 29.6-carat stone was recovered by Petra Diamonds Limited at the Cullinan mine in South Africa, the company announced on Tuesday.

"The stone is an outstanding vivid blue with extraordinary saturation, tone and clarity, and has the potential to yield a polished stone of great value and importance," the company said in a statement.

In 2013, the same company which also operates in Botswana and Tanzania, unearthed another 25.5 carat blue diamond which sold for $16.9m. It is speculated that the latest diamond discovered could also be sold for tens of millions of dollars. Such diamonds are usually sold in high-profile auctions in gatherings of some of world's richest people.

Cullinan mine, in the past, has produced hundreds of expensive large stones and is famous for its production of blue diamonds, which are among the most wanted and most expensive diamonds in the world.

"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. This stone is one of the most exceptional stones recovered at Cullinan during Petra's operation of the mine," Petra Diamonds said.

In 1905, the world's second largest cut diamond was also discovered at the Cullinan mine, which was later presented to King Edward VII. The pear-shaped 530-carat stone became part of the British crown jewels.

In 2009, a similar 26.6-carat blue rough diamond was discovered by the company, which later sold for almost $10m in an auction.

Another deep-blue diamond from the same mine was sold for $10.8m in 2012 and set a world record for the highest value per carat.