(IDEX Online) - The world's largest internally flawless diamond, a 303.1-carat fancy deep brownish-yellow stone, is to be sold without reserve at Sotheby's New York.
Bidding for the Golden Canary Diamond will start at just $1 on 7 December - a deliberate move by the auction house to provoke fierce bidding - but is expected to reach its high estimate of $15m.
It has been re-cut from the shield-shaped 407-carat Incomparable Diamond into a more traditional pear shape.
The original rough gem - an 890-carat monster - had been discarded as rubble by miners in the Democratic Republic of Congo (formerly Zaire) in the 1980s and was "rescued" by a young girl playing with her friends.
"Steeped in history, The Golden Canary is one of the most exquisite diamonds to ever be discovered, not only for its sheer size and intensity in color but for its stunning beauty that is sure to captivate collectors around the world," said Quig Bruning, head of jewelry for Sotheby's Americas.