(IDEX Online) - The world's largest internally flawless diamond, a 303.1-carat fancy deep brownish-yellow stone, sold yesterday for $12.4m at at Sotheby's New York.It became the third most valuable yellow diamond ever sold at auction, but fell short of its $15m high estimate. Sotheby's described the price as "strong".Quig Bruning, head of jewelry for Sotheby's Americas, said the Golden Canary was taking its "rightful place among the pantheon of superlative stones to be sold at auction by Sotheby's." Bidding started at just $1, a deliberate move by the auction house to provoke fierce bidding.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.It has since been re-cut from the shield-shaped 407-carat Incomparable Diamond into a more traditional pear shape.The Magnificent Jewels Sales raised a total of $50m, with 81 per cent of lots sold.Pic of Yellow Canary courtesy Sotheby's