From The Associated Press 4 May 2016:
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A London auctioneer says a diamond the size of a tennis ball that is the largest discovered in more than a century could sell for more than $70 million. ...The diamond was unearthed in November in Botswana at a mine owned by Canada's Lucara Diamond Corporation. It measured 1,109 carats, the second-largest gem-quality rough diamond ever discovered.

...The largest diamond ever found was the 3,106-carat Cullinan diamond, unearthed in South Africa in 1905. It was cut into nine pieces that form part of the U.K. Crown Jewels.
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