GABORONE, Botswana — A massive 2,492-carat diamond, the second largest in the world, has been discovered in Botswana, the Canadian mining company that found the stone announced on Thursday.

The diamond was discovered in the Karowe diamond mine in northeastern Botswana using X-ray detection technology, Lucara Diamond said in a statement.

Lucara did not provide an estimation of the value of the find. Financial Times reported that people close to Lucara estimated that the stone could be worth upward of $40 million.

In terms of carats, the stone is second only to the 3,106-carat Cullinan diamond discovered in South Africa in 1905.

"We are ecstatic about the recovery of this extraordinary 2,492-carat diamond," William Lamb, president and CEO of Lucara, said.

This find was "one of the largest rough diamonds ever unearthed" and detected using the company's Mega Diamond Recovery X-ray technology installed in 2017 to identify and preserve large, high-value diamonds, the statement said.

Naseem Lahri, managing director of Lucara Botswana, presented the translucent stone, which is the size of a palm, to Botswana's President Mokgweetsi Masisi at his office later on Thursday.

Lucara said it pays a royalty of 10 percent of the gross sales value of diamonds produced from Karowe to the government, regardless of whether the diamond is sold rough or polished.

"With a diamond of this magnitude, I can see roads being built," said Masisi, as he posed for pictures with the huge stone.

Tobias Kormind, managing director of Europe's largest online diamond jeweler 77 Diamonds, confirmed it was the largest rough diamond to be unearthed since the Cullinan diamond. Cullinan was cut into gems, some of which form part of the British Crown Jewels.

Agencies Via Xinhua