Attention Stealer: The Williamson Pink Star Diamond

September 12, 2022

By Katerina Perez

5 min read

Shout out to all gemstone lovers – a historic moment is upon us! A large coloured diamond – The Williamson Pink Star – is up for auction. Here’s why the jewellery world is abuzz with excitement and why you should pay close attention to Sotheby’s in October 2022…

We often talk about rare gemstones here at KaterinaPerez.com, but when news of an especially rare stone landed in our inboxes, we knew we had to share it. So here is everything you need to know about the upcoming auction of The Williamson Pink Star diamond:

Model wearing the Williamson Pink Star diamond, an 11.15-carat cushion-cut internally flawless fancy vivid pink diamond

Model wearing the Williamson Pink Star diamond, an 11.15-carat cushion-cut internally flawless fancy vivid pink diamond

 Model wearing the Williamson Pink Star diamond, an 11.15-carat cushion-cut internally flawless fancy vivid pink diamond

Model wearing the Williamson Pink Star diamond, an 11.15-carat cushion-cut internally flawless fancy vivid pink diamond

What is the Williamson Pink Star diamond?

The stone in question, the Williamson Pink Star, is an 11.15-carat cushion-cut internally flawless fancy vivid pink diamond. It is one of the purest and pinkest diamonds to ever appear at auction. Moreover, it is only the second of its kind to do so, being outranked by its larger predecessor, the CTF Pink Star diamond. This 59.60-carat oval mixed-cut diamond sold at Sotheby’s in April 2017 for $71.2 million and holds the world auction record for any diamond, gemstone or jewel to date. This latest gem is the epitome of nature’s finest works of art and is named after two infamous pink diamonds. The first is the previously mentioned CTF Pink Star diamond, and the second is the Williamson stone. This 23.60-carat brilliant-cut diamond was a wedding gift given to Her Majesty Queen Elizabeth II in 1947 by the Canadian geologist and royalist Dr John Thorburn Williamson. The stone was mined from the Williamson mine in Mwadui, Tanzania, one of the oldest operating diamond mines in the world, famed for producing bubble-gum-pink diamonds. The stone is now set as the centrepiece of a brooch designed by Cartier. The Williamson Pink Star diamond was cut from a 32-carat rough diamond found in the same mine.

The Williamson Pink Star diamond was cut from a 32-carat rough pink diamond

The Williamson Pink Star diamond was cut from a 32-carat rough pink diamond

Who made the Williamson Pink Star diamond?

The Williamson Pink Star diamond is natural and was therefore created by Mother Nature, deep beneath the earth. However, the natural rough was refined and polished by the multinational diamond company Diacore, a business that provides rough and polished diamonds to buyers the world over. This is not Diacore’s first foray into record-breaking diamonds. The company has created some of the world’s most famous gems, including the 203.04-carat Millennium star diamond and the 59.60-carat Pink Star diamond.

Model wearing the Williamson Pink Star diamond, an 11.15-carat cushion-cut internally flawless fancy vivid pink diamond

Model wearing the Williamson Pink Star diamond, an 11.15-carat cushion-cut internally flawless fancy vivid pink diamond

Where will the auction take place?

Sotheby’s Hong Kong will auction the Williamson Pink Star diamond. In the words of Wenhao Yu, the Chairman of Sotheby’s Jewellery & Watches, Asia: “We’re incredibly excited to offer it now in Hong Kong, which has proven to be one of the most important selling centres in the world for exceptional jewels.”

The Williamson Pink Star diamond set into a trilogy ring

The Williamson Pink Star diamond set into a trilogy ring

When will the Williamson Pink Star be auctioned?

The auction is set for this autumn. Sotheby’s Hong Kong will offer the Williamson Pink Star diamond in a standalone, single lot auction on October 5, 2022.

Model wearing the Williamson Pink Star diamond ring

Model wearing the Williamson Pink Star diamond ring

Why is the Williamson Pink Star diamond so significant? 

The discovery of a gem, let alone a coloured diamond of this quality and hue, is extremely rare. The GIA officially classifies only 5% of all natural diamonds as coloured diamonds. Furthermore, only 3% of these are considered true pink diamonds. They truly are one the rarest gems in the world, even more so since the recent closure of the Argyle mine in the East Kimberley region of Western Australia, which is said to be depleted of pink diamonds. Taking all these facts into account, this single diamond has the potential to set a world record in price per carat weight in fancy vivid pink diamonds. With the current price per carat on record at $2,656,909, the Williamson Pink Star diamond is expected to surpass $21 million in bids.

The Williamson Pink Star diamond is expected to surpass $21 million in bids.

The Williamson Pink Star diamond is expected to surpass $21 million in bids.

How are pink diamonds formed?

Perhaps a key factor in the value of pink diamonds is the air of mystery surrounding how they are created. What exactly gives pink diamonds their coveted colour has yet to be fully understood.

Model holding the 11.15-carat Williamson Pink Star diamond

Model holding the 11.15-carat Williamson Pink Star diamond

Who will purchase the stone? What fabulous piece of jewellery will they create from it? Our bets are on a gobsmacking cocktail ring or striking necklace.

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