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The ‘Perfect’ 102-Carat Oval Diamond Sold for About $16M
Offered without reserve as a “gauge of the market,” the stone’s hammer price fell well short of similar stones.

Hong Kong—The results of a Sotheby’s auction described as a true “gauge of the market” are in.
On Monday, Sotheby’s Hong Kong put a 102.39-carat D flawless oval diamond up on the auction block with no reserve price and no pre-sale estimate in a single-lot sale.
This meant the highest bid was the winning bid.
The stone ended up selling for about $15.7 million to a private buyer, falling well short of what similar stones have garnered at auction in recent years.
A 118.28-carat D color flawless oval diamond, for example, sold for $30.8 million at Sotheby’s Hong Kong in October 2013, while a pear-shaped 101.73-carat D color flawless diamond sold to Harry Winston for $26.7 million at Christie’s Geneva earlier that year.
When Sotheby’s announced the sale in September, Quig Bruning, head of the auction house’s jewelry department in New York, called the diamond “an extraordinary stone” that is “a beautiful example of a diamond.”
Sotheby’s did not reveal the name of the company that consigned the diamond for sale but did say Diacore cut and polished the stone over the course of a year from a rough diamond weighing 271 carats mined in 2018 at De Beers’ now-closed Victor Mine in Canada.
The auction house said it is one of only eight diamonds of “regular shape” (meaning modern cuts, not old mine, old European, etc.) that is over 100 carats, D color and flawless/internally flawless ever offered at auction.
View this post on InstagramA post shared by Sotheby's Jewels (@sothebysjewels) on Sep 23, 2020 at 7:49pm PDT
Though the auction featured a live component Monday in Hong Kong, Sotheby’s had been taking online bids for the stone since mid-September.
It confirmed the highest online bid for the oval diamond was nearly $11 million, which it said is the largest bid ever placed for a jewel online.
But the winning bid ended up coming over the phone from a private collector in Japan, who renamed the diamond the “Maiko Star” after his second daughter, continuing a family tradition of sorts.
The same buyer also purchased an 88.22-carat oval diamond for nearly $14 million in April 2019 that he named the “Manami Star,” after his eldest daughter.
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