Historic gem: World's largest flawless diamond up for auction

A 163.41-carat D flawless diamond, described as the largest ever put up for auction, was unveiled in Hong Kong on Thursday.

‘D’ graded diamonds are colorless.

The diamond, unveiled by jewelry specialist de Grisogono, is cut from a 404.2-carat stone named the “4 de Fevereiro” that was discovered in Angola in February 2016. The stone is the 27th largest rough white diamond ever discovered and the largest in Angola, according to de Grisogono.

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After analysis in Antwerp, the rough diamond was cut in New York, where a team of 10 specialists turned it into a 163.41-carat emerald-cut stone.

In this image released on Thursday, Sept. 28, 2017, a diamond necklace featuring a 163-carat flawless emerald stone, the largest of its kind ever to be put up for auction, has been unveiled in Hong Kong today. The finished piece, named The Art of de Grisogono will be presented in a series of public viewings around the world before it goes up for an auction at Christie's in Geneva on November 14. For further information visit http://www.apmultimedianewsroom.com/newsaktuell. (Actua Films via AP Images)

In this image released on Thursday, Sept. 28, 2017, a diamond necklace featuring a 163-carat flawless emerald stone, the largest of its kind ever to be put up for auction, has been unveiled in Hong Kong today. The finished piece, named The Art of de Grisogono will be presented in a series of public viewings around the world before it goes up for an auction at Christie's in Geneva on November  (Actua Films via AP Images)

De Grisogono then suspended the stone from a diamond baguette necklace, from which it can be detached. The finished jewelry piece, named The Art of de Grisogono, will now be taken on a world tour, visiting London, Dubai and New York before it goes up for auction in Geneva, Switzerland on Nov. 14.

In 2015 a ‘perfect’ 100-carat flawless D diamond was sold at Sotheby’s New York for $22 million, including the buyer’s premium.

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An uncut diamond the size of a tennis ball sold for $53 million Tuesday. British jeweler Graff Diamonds bought the 1,109-carat stone, the Lesedi La Rona, which was mined in Botswana in 2015.

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