By Rajini Vaidyanathan . BBC News. 27.apr.2009
A rare blue diamond which could set a world record price per carat when it is sold in May has gone on show in London.
Smaller than a penny piece, it is worth between $5.8m (£3.9m) and $8.5m (£5.7m) according to estimates by its sellers.
It weighs 7.03 carats and is one of only a handful of blue diamonds in existence in the world.
The diamond was found in South Africa last year and is on show at Sotheby’s, in Mayfair, until Tuesday. It will be auctioned in Geneva on 12 May.
The gem, which was cut from a 26.58 carat rough diamond, was discovered in 2008 at the Cullinan mine.