This vivid blue diamond, which“is among the most beautiful coloured diamonds ever offered at auction”, according to Rahul Kadakia, International Director of the Jewellery Department at Christie's, had been estimated by the auction house at between $20 and $30 million.

It sold under the hammer for CHF17.4 million, for a final price of $25,592,269 including taxes, according to Christie's. The same stone, then known as the Zoe Diamond, sold for $32.6 million at Sotheby's in New York in 2014, setting world records at the time for a blue diamond and for price per carat.

For decades, the stone belonged to Rachel Lambert Mellon, better known as 'Bunny' Lambert Mellon (1910-2014), an American horticulturist, philanthropist and art collector. The stone was then mounted as a pendant.

Bunny Mellon is best known for redesigning the White House Rose Garden in 1961 at the request of President John F. Kennedy.

The highest price ever achieved by Christie's for a vivid blue diamond was set in Geneva in 2016 when 'Oppenheimer Blue' (14.62 carats) sold for $57.5 million.

Translated from French by DeepL/mga

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