Only three fancy vivid blue diamonds over 10 carats in weight have come up for sale at Christie's auction house since the company was founded in 1766.
An exceptionally rare blue diamond went under the hammer in Geneva Tuesday, selling for more than $40 million, making it one of the most expensive diamonds ever sold at auction, Christie's said.Fancy vivid blue diamonds weighing more than 10 carats are exceptionally rare.
An exceptionally rare blue diamond went under the hammer in Geneva Tuesday, selling for more than $40 million, making it one of the most expensive diamonds ever sold at auction, Christie s said.