A 2,492-carat rough diamond discovered in Botswana is considered the second largest gem-quality diamond ever unearthed after the famous Cullinan Diamond.

The gigantic gemstone was found in the Karowe diamond mine in Botswana, which is wholly owned by Canadian mining company Lucara Diamond Corp.

“We are thrilled with the discovery of this exceptional 2,492-carat diamond,” Lucaras President William Lamb said in a statement.

Lucara did not disclose details about the quality or value of the diamond. However, the Financial Times cited anonymous sources close to Lucara who estimated that the diamond could fetch over $40 million.

The diamond was discovered and recovered using the company’s Mega Diamond Recovery (MDR) X-ray Transmission (XRT) technology, which was installed in 2017 to identify and preserve large, high-quality diamonds. Lamb said the discovery validates Lucara’s investment in XRT technology as well as the potential of its Karowe mine, which has produced some huge finds in recent years.

In 2019, a 1,758-carat diamond found in the mine was purchased by luxury fashion brand Louis Vuitton. Previously, in 2010, Graff Diamonds bought the 1,109-carat diamond found in Karowe in 2016 for a staggering $53 million.

“This discovery reinforces Karowe’s position as a truly world-class diamond mine and underscores the continued success of our operational and underground development strategy,” said William Lamb.

The Cullinan Diamond remains the largest gem diamond ever discovered at 3,106 carats. It was mined in South Africa in 1905 and cut into several smaller stones.