An Astonishing Diamond Discovery in Botswana

Last week, a diamond company announced a remarkable discovery found in a mine in Botswana: the second-largest gem-quality diamond ever found on earth, second in size only to the magnificent Cullinan Diamond.

A press release from Lucara Diamond, a corporation based in Canada with mining operations located in southern Africa, announced the spectacular discovery: “Lucara Diamond Corp. is thrilled to announce the recovery of an exceptional 2,492 carat diamond from its Karowe Diamond Mine in Botswana. This remarkable find, one of the largest rough diamonds ever unearthed, was detected and recovered by the Company’s Mega Diamond Recovery (“MDR”) X-ray Transmission (“XRT”) technology, installed in 2017 to identify and preserve large, high-value diamonds.”

The New York Times noted, “Such whopping stones are no longer once-in-a-lifetime finds thanks to evolving technology. Lucara spotted an opportunity in Botswana when it dug up large quantities of small but coarse stones that looked like “chewed glass,” said William Lamb, the company’s chief executive. It was a hint that larger diamonds were probably being crushed in the retrieval process.” Lucara has employed its diamond recovery technology to separate gemstones from other minerals. In this case, the diamond was recovered during the processing of kimberlite, the igneous rock that is the main host matrix for diamonds.

The increasing frequency of discovery of these enormous diamonds in Botswana is seen by many as a promising sign for the country’s economy. The 2,492-carat diamond fills the palm of an adult’s hand, as was evident when the President of Botswana, Mokgweetsi Masisi, posed with the stone on Thursday.

The yet-unnamed diamond, pictured again above with objects for comparison, is the second-largest gem-quality diamond ever discovered, after the Cullinan Diamond. Both would have been eclipsed by the largest natural diamond ever discovered: the Sergio, a 3,167 stone discovered in 1895 in Brazil that is thought to have been part of a meteorite. That stone, which was not a gem-quality diamond, was sold and broken into small pieces for use in industrial drilling.

Let’s have a look at the five largest gem-quality diamonds known to have been found on earth, shall we? The largest of them all is still the 3,106-carat Cullinan Diamond, found in the Premier Mine in South Africa in 1905. The diamond was offered for sale, but after no takers in two years, it was purchased by the Transvaal colonial government in 1907, who decided to present it to King Edward VII.

The King accepted the diamond at Sandringham, announcing that he intended for the gems that were cut from the rough stone to be part of the Heirlooms of the Crown. The cutting was done in Amsterdam by Joseph Asscher. Nine major stones were produced. The largest two were set in the British crown jewels, and the other seven all ended up with Queen Mary, who left them to Queen Elizabeth II. Today, they’re in the collection of King Charles III.

Taking second place on the list now is the 2,492-carat diamond recently found at the Karowe mine. The diamond is also, of course, currently the largest diamond ever mined in Botswana, though the people at Lucara have ambitions to continue to break that record. Indeed, the Lucara CEO, William Lamb, told the New York Times, “We believe that we can eclipse the Cullinan.”

They’re well on their way. Lucara actually holds the distinction of having found diamonds 2-5 on the top five list, all of which were discovered at the Karowe Mine. (If you expand the list to the top ten gem-quality stones, Lucara can take credit for six of the ten.) The third-largest diamond on the list is the Sewelô Diamond, a 1,758-stone found at the Karowe Mine in April 2019. The diamond was acquired in 2020 by Louis Vuitton, who plan to have it cut in Antwerp. The diamond may not be considered by some to be “gem-quality,” because it is classed as a diamond that is anticipated to produce gem-quality stones. Lucara described it as a “near-gem of variable quality, including domains of high-quality white gem.”

The fourth-largest gem-quality diamond on the list is the 1,174-carat diamond found in the Karowe Mine. Calling this one gem-quality may also be a stretch: an official press release from Lucara describes it as “a clivage gem of variable quality with significant domains of high-quality white gem material.”

The fifth-largest diamond on the gem-quality list is the 1,111-carat Lesedi La Rona, found at the Karowe Mine on November 16, 2015. This one definitely is gem-quality, and its name means “our light” in Tswana, a Bantu language spoken in southern Africa.

After a failed attempt to auction the stone at Sotheby’s in 2016, the gem was purchased for a whopping $53 million by Graff. They had it cut in 2019, producing one large diamond and 66 smaller stones. The resulting large gem is the world’s largest emerald-cut diamond, dubbed the Graff Lesedi La Rona, weighing in at an astonishing 302.37. The 66 other stones produced from the rough diamond range in size from 26 carats to less than one carat.

Here’s one more look at the diamond found recently in Botswana. It’s tough to even conceptualize a diamond that weighs more than 2,000 carats! It’s going to be interesting to trace the path of this stone going forward.