Although overall diamond prices are down, the sales for the big and rare stones are still pretty strong. Petra Diamonds, a miner of stones in Africa, is hoping for a high number for their first sale of a cut and polished stone through Sotheby's. They will be selling a 7.03-carat blue diamond
from the Cullinan mine in South Africa. The Cullinan mine has yielded most of the best blue diamonds in the world. The stone has a fancy vivid blue color and is rated internally flawless. Petra decided to sell the stone as cut and polished versus selling the rough as they usually do because they are hoping to get maximum exposure for the gem.
The stone will be shown in Hong Kong, Paris, New York and London before winding up in Geneva for the Sotheby's auction on May 12
. It is estimated to sell for as much as $8.5 million. Maybe the stone will appeal to famous diamond dealer Laurence Graff. Last December he picked up the Wittelsbach diamon
d, a grayish-blue 35.56 carat stone with an impressive historical provenance, for $24.3 million making it the world's most expensive blue diamond.