Rare pink diamond sells for US$57m in Hong Kong auction

A rare diamond, described in the auction catalogue as “fancy vivid pink” has been sold for 453 million Hong Kong dollars (US$57 million) – more than double its estimate – a world record for a diamond sold at auction.

The UK’s Guardian newspaper reports that the 11.15-carat Williamson Pink Star is named after another pink diamond, simply “the Williamson” given to Queen Elizabeth II as a wedding gift. It was sold to an anonymous buyer by Sotheby’s Hong Kong on Friday. The stone’s connections to the late queen are likely to have helped its value.

Mounted on a floral brooch designed by Cartier in 1953, the Williamson was said to have been a favourite of Queen Elizabeth, who wore it on many occasions during her reign, including the silver jubilee.

Some of the world’s highest quality diamonds have seen prices double over the past 10 years against the backdrop of an unstable global economy. Prices have surged as sanctions on one of the world’s two biggest miners take effect. Diamond cutters, polishers and traders are struggling to source stones after the US levied sanctions on Alrosa PJSC, which accounts for about a third of global production.

The Williamson Pink Star is one of only two flawless ‘fancy vivid pink’ diamonds over 10 carats to appear at auction. It is thought to have been the inspiration for the Pink Panther diamond in the 1963 film of the same name.

John Thoburn Williamson was a Canadian geologist who established the Williamson diamond mine in present-day Tanzania and owned the Mwadui mine where the stones were discovered. He gave the uncut stone to Princess Elizabeth and Prince Philip upon their wedding in November 1947.

Wenhao Yu, the chair of jewellery and watches at Sotheby’s Asia, said…

“The discovery of a gem-quality pink diamond of any size is an extremely rare occurrence, something that – with the recent closure of the Argyle mine – seemed, until recently, highly improbable.”

While nitrogen and boron provide the colour of yellow and blue diamonds, there is no evidence that pink diamonds receive their colour from trace elements.