Diamond Auction Rare Vivid Blue Diamond Goes On Auction In Geneva.

It is one of the rarest diamonds available on the market that will go under the hammer in Christie's semi-annual auction in Geneva in one-week's time.

Estimated between 38 million US dollars and 45 million US dollars, the rectangular-cut "Oppenheimer Blue" weighs 14.62 carats, and has been graded by the gemological institute of America as "Fancy Vivid Blue", meaning its blue color ranges from medium to dark in tone, and from strong to very strong in saturation, without presence of any other tint, like grey for instance which is commonly observed in blue diamonds.

Its provenance, according to Lunel, adds to its prestige and also gives it an historical interest, as it used to be previously owned by Sir Philip Oppenheimer who belonged to the family who ran the De Beers Mining Company.

De Beers had a monopoly in extracting and commercialising diamonds in the 20th Century.