GENEVA.- Christie's presents THE MELLON BLUE, the first jewellery highlight of the second half of 2025 to come to auction. THE MELLON BLUE, an exceptional Fancy Vivid Blue diamond, weighing 9.51 carats, graded Internally Flawless and recently set as a ring, will lead the Magnificent Jewels live auction taking place on 11 November at the Four Seasons Hotel des Bergues in Geneva. It is a rare expression of nature's brilliance and remarkable for both its intense colour and its extraordinary purity. One of the finest coloured diamonds to appear on the market (estimate $20,000,000 – 30,000,000), for decades, the stone - then set as a pendent - belonged to Rachel Lambert Mellon, better known as Bunny Mellon (1910-2014), an American horticulturalist, philanthropist, and art collector. Bunny Mellon was a symbol of elegance and sophistication, and her refined taste extended to her jewellery, which she selected with the same care and sensitivity she brought to her interiors and gardens. The diamond was last seen publicly in 2014 when it was offered at auction in New York, achieving one of the highest prices paid for a coloured diamond at auction.

To this day Bunny Mellon's horticultural vision can be admired at the White House in Washington. In 1961, President John F. Kennedy asked Mellon to redesign the White House Rose Garden where Mellon created more open space for public ceremonies and introduced American species of plants to the garden. Elsewhere, in France, Mellon created a landscape design for the home of Hubert de Givenchy, who was a close friend, and assisted with the restoration of the “Potager du Roi” at the Chateau de Versailles.

Rahul Kadakia, Christie's International Head of Jewellery, comments: “'Christie's has sold nine of the top 10 jewels at auction in the first half of the year, driving year on year growth by 25%, with two various owner live auctions selling 100% in New York and in Geneva. We are now looking confidently to the second half of 2025 by announcing “THE MELLON BLUE”. This stunning Fancy Vivid Blue Diamond, once belonging to America's Garden Queen, and is among the finest coloured diamonds to appear for sale at auction.“

The stone will be previewed in advance of the auction in Geneva:

23 - 28 October at Christie's Hong Kong
07 - 11 November at the Four Seasons Hotel des Bergues in Geneva