A fancy deep-blue diamond weighing 5.30 carats set a $1.8 million per carat world record at Bonhams Fine Jewelry sale in London last week. The selling price of approximately $7.3 million was more than five times its pre-sale estimate.
The antique cut cushion shaped blue beauty is mounted in a Trombino ring surrounded by pavé-set round brilliant cut and baguette cut white diamonds approximately 2.00 carats total. The Gemological Institute of America (GIA) has graded the diamond as fancy deep blue, natural colour and VS2 clarity.
“Blue diamonds, especially those over 5 carats, are extremely rare to see on the market and continue to be highly sought after,” said Jean Ghika, director of Bonhams jewelry department for Europe.
The term ‘fancy’ describes the Type IIb diamond’s unique shade of blue which stems from traces of Boron elements. Other historic blue diamonds which exhibit similar characteristics include the Hope diamond, the Wittelsbach-Graff diamond and the Tereschenko diamond. All are believed to have originated from the Golconda mines which have produced white diamonds and fancy color diamonds with the highest degree of brilliance.