Magnificent and Exceptionally Rare Fancy Deep Blue diamond

The fancy deep blue briolette diamond weighing 10.48 carats.

Please refer to GIA report for details on the diamond.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Please note that colour, clarity and weight of gemstones are statements of opinion only and not statements of fact by Sotheby's. We do not guarantee, and are not responsible for any certificate from a gemological laboratory that may accompany the property. We do not guarantee that watches are in working order. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue, in particular to the Notice regarding the treatment and condition of gemstones and to the Notice regarding import of Burmese jadeite and rubies into the US.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD "AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

By definition, a precious gemstone must be beautiful, rare
and durable. These criteria are more than fulfilled by the
exceptional diamond shown here: a magnificent Fancy
Deep Blue.

Diamonds are found in a variety of colours, each shade determined by their atomic structure. The blue diamond presented as lot 435- which to use the correct terminology is a Fancy Deep Blue – is an
exquisite example, unsullied by secondary colours. Scientifically speaking the blue is due to the replacement of carbon atoms by
boron in the crystal lattice of the stone, effecting its absorption of colour. Looked at emotionally, however, this stone is truly beauty personified. Cut as a superb drop-shaped briolette, its many facetted surface, designed to reflect and refract light, has the added virtue of being flawless and, in terms of polish and symmetry, has been awarded the highest possible grade by the Gemological Institute of America.
In Hong Kong recently, Sotheby's set a per-carat world record for any gemstone at auction when a superb 6.04 carat Fancy Vivid Blue emerald-cut diamond sold for HK$10 ($1.3) million per carat. This figure was narrowly exceeded by Sotheby's in Geneva this May when a 3.73 carat similarly coloured diamond sold for SF1,394,369 ($1,321,927) million per carat. Given this history of selling blue
diamonds, this exceptionally large and exquisite gem is certain to attract attention.