It brought the total for Christie's Geneva auctions in 2017 to $258,588,868, with 27 lots sold for over $1 million.
Called The Art of Grisogono, the 163.41-carat diamond - attached to an emerald and diamond necklace - was sold to an unnamed telephone bidder at the Christie's autumn jewel auction in Geneva, Switzerland.
Geneva jewellers de Grisogono then took on the task of transforming the massive diamond into a piece of wearable jewellery.
The stone was 404.20 carats when it was a rough diamond mined in eastern Angola on 4 February past year. He began splitting the rough diamond into two in June a year ago and eventually polished the diamond down to an emerald-cut.
"I am disappointed that the Art of De Grisogono didn't sell for a more dazzling price", said Tobias Kormind, head of 77Diamonds.com, a London-based online jeweller. It took more than 1700 hours to create.
Set in an emerald and diamond necklace, the massive gem had been on tour to Hong Kong, London, Dubai and NY.More news: Trump meets Japan, Australia leaders, discusses trade, North Korea threat
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Mr Gruosi and his team eventually came up with an asymmetric necklace featuring 18 emerald-cut diamonds on one side with the 163.41-carat diamond as the centrepiece.
The stone up for sale Tuesday is meanwhile a "much larger diamond, and its title of the largest flawless stone could see it attract a winning bid of over $50 million", he suggested.
Le Grand Mazarin was up for auction for the first time in 130 years, during a sell-off of French crown jewels.
The gem was named after Cardinal Mazarin, an Italian cardinal and diplomat, as well as a great art collector, who served as chief minister under Louis XIII and Louis XIV, and who bequeathed it and other diamonds to the Sun King in his will.
The stone was 40% bigger than a diamond Sotheby's sold in 2013 for about $31m, he said.