The blue diamond was sold for R$134.4 million at an auction in Switzerland; photo

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The value of the bright blue diamond, which is “one of the most beautiful colored diamonds ever put up for auction,” according to Rahul Kadakia, international director of the jewelry department at Christie’s, was estimated at between $20 and $30 million.

The stone was sold for 17.4 million Swiss francs, bringing its final price to $25.5 million after taxes, according to Christie’s.

The same gem, then known as the “Zoe Diamond,” sold for $32.6 million at Sotheby’s in New York in 2014, setting records for a blue diamond.

The stone was owned for decades by Rachel Lambert Mellon, known as Bunny Lambert Mellon (1910-2014), an American horticulturist, philanthropist and collector of art. At that time, it was mounted on a pendant.

Bunny Mellon is also remembered for the restructuring of the White House Rose Garden, undertaken in 1961 at the request of President John F. Kennedy.

The highest price achieved by Christie’s for a vivid blue diamond was set in Geneva in 2016, when a 14.62-carat Oppenheimer Blue diamond sold for $57.5 million.