CNN  — 

The largest white diamond to ever come up for auction has been sold for 21,681,000 CHF ($21.9 million) at Christie’s in Geneva.

The 228.31-carat, pear-shaped gemstone – dubbed “The Rock” – originated from South Africa, where some of the largest diamonds in the world have been found, including the pear-shaped “Star of Africa” and rose cushion cut “Golden Jubilee.”

“The Rock” is about the size of a golf ball and was previously worn as a lavish Cartier necklace by its former owner. Along with the pear-shaped stone, the new owner will also receive a round diamond and platinum pendant mounting from the French luxury brand.

Ahead of the sale, the head of Christie’s jewelry department in Geneva, Max Fawcett, explained why “The Rock” is a particularly unique stone.

“Often with these largest stones, they sacrifice some of the shape in order to keep the weight,” he told Reuters. “This is a perfectly symmetrical pear-shape form and… one of the rarest gems ever to be sold at auction.”

A 228.31 carat white diamond called "The Rock."

Despite its grandeur, the hammer price of “The Rock” fell short of its low estimate during the quick bidding period Wednesday. The auction house had given the diamond a 30,000,000 CHF ($30.2 million) high estimate. In 2017, an intricate emerald and diamond necklace from Swiss luxury jeweler de Grisogono, which featured a central 163.41-carat rectangular sparkler, set the record for a white diamond sale at 33,500,000 CHF ($33.8 million USD).

But other lots in the “Magnificent Jewels” sale smashed expectations, including a 1940s pink sapphire, ruby and diamond brooch mounted by Cartier, which sold for 579,600 CHF ($585,000) – over 11 times its high estimate – and a 19th-century diamond and pearl tiara, which sold for more than triple its high estimate at 2,394,000 CHF ($2.4 million).

The final lot was a diamond that is nearly as large as “The Rock” – the 205.07-carat, yellow cushion-shaped stone named “The Red Cross Diamond.” That gem sold for 14,181,250 CHF ($14.3 million), a portion of which will be donated to the Geneva-based International Committee of the Red Cross (ICRC). First sold at Christie’s over a century ago to help the British Red Cross during World War I, the diamond was estimated to sell for between $7 million and $10 million, according to Fawcett.