Canadian mining company Lucara Diamond Corp announced it had unearthed a massive 2,492-carat (or 498.4-gram) stone at its Karowe Diamond Mine in northeastern Botswana, with President Mokgweetsi Masisi posing with the giant diamond on Thursday. 

It's most likely the second-largest diamond ever found within the Earth, after the 3,106-carat Cullinan diamond found in South Africa in 1905. 

A larger black diamond was also found above ground in Brazil in the late 1800s, but that is believed to have been part of a meteorite.

Lucara did not estimate the diamond's value or comment on its quality but called it "one of the largest rough diamonds ever unearthed." 

New X-ray technology seeks to identify large diamonds before extraction

Lucara said that the diamond was detected and recovered using what it calls its "Mega Diamond Recovery X-Ray Transmission" technology, which it installed in 2017.

The idea is to identify large stones within the rock prior to mining, and then to avoid unknowingly damaging or breaking them into pieces during extraction, which used to be a common pitfall for the industry.

"We are ecstatic about the recovery of this extraordinary 2,492-carat diamond," Lucara President William Lamb said in the statement.

"This find not only showcases the remarkable potential of our Karowe Mine, but also upholds our strategic investment in cutting-edge [X-Ray Transmission] technology. The ability to recover such a massive, high-quality stone intact demonstrates the effectiveness of our approach to diamond recovery and our commitment to maximizing value for our shareholders and stakeholders."

Tobias Kormind, managing director of 77 Diamonds, Europe's largest online diamond jeweler, told the AFP agency that, given this new technology, "we will likely see more where this came from" in the future.

Botswanan President Masisi among first to hold the stone

President Mokgweetsi Masisi's government described the diamond as the second largest in the world, and Masisi posed with the gemstone on Thursday in his office in the capital Gaborone. 

The diamond mining industry is crucial for Botswana, with the stones accounting for well over half the financial value of the country's total exports.

Lucara said in its statement that the diamond industry "delivers wide-ranging socio-economic benefits to the country that extend well beyond the mining sector," citing "critical areas such as education and healthcare" as beneficiaries.

This is the third very large diamond unearthed at the Karowe mine in recent years. The 1,758-carat stone unearthed in 2019 was previously the largest ever mined in Botswana and was named Sewelo, meaning "rare find" in the Setswana language. The Karowe mine also extracted a 1,174-carat diamond in 2021 using the same X-ray technology.

msh/ab (AFP, AP)