UPDATE: One of only four 1,000 carat-plus diamonds ever found dug up in Botswana

Debswana Diamond, a joint venture between De Beers and the government of Botswana, has found a 1,098-carat stone, one of only four rocks over 1,000 carats ever unearthed, and the biggest by the company since it began operations five decades ago.

The yet to be named massive stone was picked on June 1 at Jwaneng, the world's richest diamond mine by value, which is undergoing a US$2 billion expansion.

Initial analysis suggests the diamond is close not only in size, but also in quality to the 3,106-carat Cullinan, discovered in South Africa in 1905; the 1,758-carat Sewelo, unearthed at Lucara's Karowe mine in Botswana in April 2019; and the 1,111 Lesedi la Rona, also found in Botswana in 2015.

Considering only white diamonds, the fresh discovery would be the world's third-largest.

The yet-to-be-named massive stone was picked June 1 from a refuse bin at Jwaneng, the world's richest mine by value. (Image courtesy of Duma Radio | Twitter.)

"We will work with the government of the Republic of Botswana and De Beers to value and sell the diamond to ensure it returns maximum benefit for the people of Botswana," said Debswana spokesperson Rachel Mothibatsela in a media statement.

Early reports claimed the diamond, which measures 73 mm long, 52 mm wide and 27 mm thick, had been found in a refuse bin at Jwaneng. Debswana Diamond said those reports were incorrect.

Botswana, Africa's leading diamond producer, is used to having an influx of international diamond buyers from Mumbai and Antwerp and traders from China.

Recently, however, the country decided to close its Damtshaa diamond mine for three years due to weak demand and trading disruptions caused by the ongoing global pandemic.

Debswana, a 50/50 partnership between Botswana and De Beers, provides the country with around two-thirds of its foreign exchange and contributes a fifth of its GDP.

In 2021, Debswana plans to increase output by as much as 38% to pre-pandemic levels of 23 million carats as the global diamond market recovers with the easing of travel restrictions and reopening of in-person sales.

Jwaneng is critical to De Beers as it contributes nearly half the carats the company produces per year. In 2020, the mine yielded 7.5 million carats of the group's 2020 output of 25.1 million carats.