In Geneva, Sotheby's auctioned the most expensive jewel in the world to a Hong Kong buyer. The sale set a record for price per carat (over €4 million per carat). "This is a record price for a precious stone and per carat", David Bennett, Global President of the international jewellery department of Sotheby's.

The 12-carat blue stone was discovered in January 2014 by Petra Diamonds Ltd in the Cullinan mine (photo) in South Africa. According to Sotheby's, the Cullinan mine is "the only reliable source in the world for blue diamonds".

In February 2014, Petra Diamonds Ltd, listed on the London Stock Exchange, sold this exceptional blue diamond of 29.62 carats for USD 25.555 million.