Hong Kong CNN  — 

On Monday evening an exceptionally rare 102.39-carat diamond made auction history as the first gem of its quality to be sold without a reserve.

With a live auction taking in online and phone bids, the opening price was $0.13, but eventually climbed to the winning bid of $15.7 million.

Cut from a rough diamond discovered in 2018 in Ontario, Canada, the oval stone received the highest bid placed for a jewel online, nearly $11 million, but eventually went to a telephone bidder in Japan, a private collector who quickly called the stone “Maiko Star” after one of his daughters. This same collector purchased a diamond from Sotheby’s last year, naming it “Manami Star” after his eldest daughter.

Patti Wong, the chairman of Sotheby’s Asia said in a press release that the “extraordinary gem needed no help from a pre-sale estimate or reserve to reach its rightful price – just the instinctive desire of collectors to own one of the earth’s greatest treasures. And that the sale is a testament “not just to the importance of this diamond, but to the market for diamonds more broadly.”

While Sotheby’s had declined to provide a pre-sale estimate, the auction house had been expected to attract huge bids for the item after it achieved top rankings in each of the “four Cs” by which a diamond is judged – cut, color, clarity and carat weight.

The stone had also been classified as “D color,” the highest grading for a white diamond. It is considered to be internally and externally “flawless” – placing it among the world’s most chemically pure, transparent and symmetrical diamonds – and it belongs to a rare subgroup of diamonds that contain little to no nitrogen.

The stone was only the eighth white diamond of comparable size and quality to sell at auction, according to Sotheby's.

Only seven D color flawless (or internally flawless) diamonds weighing more than 100 carats had ever appeared at auction before Monday’s sale, according to Sotheby’s.

Of these, the most expensive remains a rectangular 163.41-carat diamond, which sold for $33.7 million at Christie’s in Geneva, while the record sum for an oval variety still stands at $30.8 million in 2013.

‘Transformative’ time for auction market

Unusually, the rare oval diamond at Monday’s sale was offered without a reserve, meaning that it would have been sold regardless of the size of the highest bid.

Prior to the sale, the item was displayed at appointment-only previews in Beijing, Shanghai, New York and Taipei. Bidding had been open online for almost three weeks before the sale was concluded at Monday’s live auction.

In a press statement released ahead of the auction, Sotheby’s worldwide chairman of jewelry, Gary Schuler, had said that it was “difficult to overstate (the stone’s) rarity and beauty.” Chair of Sotheby’s Asia, Patti Wong, meanwhile expressed confidence about the sale, despite the challenges presented by the Covid-19 pandemic, in what she called “deeply transformative months for the auction market.”

The stone was from a larger, 271-carat rough diamond discovered at the Victor Mine in Ontario, Canada.

“Diamonds of this caliber attract interest well beyond the traditional pool of collectors,” Wong said, adding that the sale would “act as a great indicator of the vitality of the demand.”

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This is the most expensive diamond sold at an online auction
00:45 - Source: CNN

While white diamonds can attract huge bids at auction, pink and blue varieties have achieved even larger sums in recent years. In 2017, a 59.60-carat pink diamond known as the Pink Star became the most expensive jewel ever to sell at auction when it went for $71.2 million at Sotheby’s in Hong Kong.

Two years earlier, the 12.03-carat “Blue Moon” diamond sold for $48.4 million, also through Sotheby’s.

This article was originally published on September 12, 2020. It was updated to reflect the auction result.