Rare Pink Star diamond 'to set auction record'
25 September 2013 Last updated at 17:28 BST
A flawless 59.6-carat pink diamond is to be auctioned in the Swiss city of Geneva at a record asking price of $60m (£38m).
Sotheby's David Bennett says the diamond belongs in "the ranks of the earth's greatest natural treasures".
Imogen Foulkes took a close look at the diamond.