World's largest orange diamond to be auctioned in Genev

A spectacular and rare orange diamond, the largest known gem of its kind, will go under the hammer in Geneva Tuesday, with auctioneers hoping it will fetch at least $20 million.

The fiery almond-shaped diamond, nicknamed "The Orange" has been travelling the world in recent weeks to help Christie's evaluate how much of a buzz it might cause.

"There's been a lot of interest, as one could imagine with something so rare," Christie's international jewellery director David Warren told AFP.

The deep orange gemstone, which was found in South Africa, weighs a whopping 14.82 carats, and the Gemological Institute of America (GIA) has handed it the top rating for coloured diamonds: "fancy vivid".

Pure orange diamonds, also known as "fire diamonds", are exceptionally uncommon and very few have been auctioned, with the largest never more than six carats.

"To have one that’s over 14 carats is exceptional," Warren said, pointing out that "The Orange" "is in fact the largest recorded vivid orange diamond in the world."

Rare and expensive 'freaks of nature'

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