The stone was sold for US$9,488,754 making its price per carat US$1,349,752; the highest price ever paid for a fancy vivid blue diamond sold at auction.
Collector Joseph Lau Luen-Hung, the Hong Kong buyer of the Cullinan blue diamond, has already named the record-breaker “Star of Josephine”.
The lustrous blue stone ranks among the most important diamonds ever to be offered for sale by Sotheby's.
The “Star of Josephine”, weighing 7.03 carats, was cut from a 26.58 carat rough diamond found in 2008 in the historic South African mine of Cullinan.
When speaking about the stone, Petra Diamonds' chief executive Johan Dippenaar has this to say, "The renowned Cullinan mine continues to captivate the world with spectacular diamonds, building on its legacy as the source of some of the world's most famous gems."
Dippenaar went on to add that the price achieved for the stone reflected how rare and collectable such an important blue diamond is to the connoisseur.
As the jewellery world turns its focus from the traditional purity of white diamonds, coloured gemstones and especially diamonds have stepped into the limelight as the must-have jewels of the moment.
The important sale of Petra's flawless blue diamond has proved that beyond a shadow of a doubt.