lucapa diamond

A rare pink diamond of 170 carats discovered in Angola is thought to be the largest such gemstone found in 300 years.

Called the Lulo Rose, the diamond was found at the Lulo alluvial diamond mine, the mine’s owner, the Lucapa Diamond Company, announced on its website.

“Only one in 10,000 diamonds is coloured pink. So you’re certainly looking at a very rare article when you find a very large pink diamond,” Lucapa chief executive Stephen Wetheral said.

The pink gemstone is expected to fetch a high value when auctioned, but Mr Wetherall said he does not know what kind of premium will be paid because of its colour.

Lulo is an alluvial mine which means the stones are recovered from a river bed.

The Lucapa company is searching for the underground deposits, known as kimberlite pipes, which would be the main source of the diamonds, said Mr Wetherall, speaking from the company’s headquarters in Australia.

“We’re looking for the kimberlite pipes that brought these diamonds to the surface,” Mr Wetherall said.

“When you find these high-value large diamonds … it certainly elevates the excitement from our perspective in our hunt for the primary source.”

About 400 staff are employed at the Lulo mine, which has already produced the two largest diamonds ever found in Angola, including a 404-carat clear diamond, he said.

The pink gemstone is the fifth largest diamond found at the mine, where 27 diamonds of 100 carats or more have been found, according to Lucapa.

The pink diamond will be sold by international tender by the Angolan state diamond marketing company Sodiam.

Similar diamonds have been bought for tens of millions of dollars in the past, with one – known