GENEVA, SWITZERLAND — A 163-carat diamond, the largest of its kind to go under the hammer, realized $33.7 million at Christie’s auction at Geneva’s Four Seasons Hotel on November 14.

The colorless diamond was taken from a 404-carat stone found in Angola, and was finished into a piece comprising white gold, the diamond and emeralds.

Christie’s said the necklace was designed by Swiss jewelry maker de Grisogono and took more than 1,700 hours to make.

The identity of the purchaser of the necklace, named “The Art of de Grisogono,” was not revealed.

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