THE Pink Legacy, an exceptionally large pink diamond, is set to go under the hammer at Christie’s in Geneva today, when it is expected to bring in up to US$50 million.

At nearly 19 carats, the vividly colored gem is extraordinary, Jean-Marc Lunel, an international jewelry specialist at Christie’s, said.

“If you consider that most pink diamonds weigh less than a carat, it is really something,” he said.

The gem, which today will be offered at auction for the first time, has been estimated at between US$30 million and US$50 million, and Lunel suggested it could hit the high end of that range.

“It is probably the most beautiful [specimen] ever presented at public auction,” he said.

The rectangular-cut diamond has been graded “fancy vivid” — the highest possible grade of color intensity.

Christie’s pointed out that in the salesroom, fancy vivid pink diamonds over 10 carats are “virtually unheard of” and that only four vivid pink diamonds over 10 carats have ever been offered for sale at auction.

One of them, the nearly 15-carat Pink Promise, was sold last November at a Christie’s auction in Hong Kong for US$32.5 million. That amounts to US$2.176 million per carat, which remains the world auction record price per carat for any pink diamond.

And in 2013, a huge pink diamond weighing 59.60 carats meanwhile went under the hammer at Sotheby’s for US$83 million, or US$1.39 million per carat.

The Pink Legacy used to belong to the Oppenheimer family, which for decades ran the De Beers diamond mining company, but Christie’s refused to say who the current owner was.

It was discovered in a South African mine around a century ago, Lunel said.

“It was probably cut in the 1920s,” he said, adding that it had not been altered since.

Rahul Kadakia, Christie’s international head of jewelry, meanwhile said in a statement in September that the Pink Legacy’s exceptional provenance will no doubt propel it into a class of its own as one of the world’s greatest diamonds.

(SD-Agencies)