The two large, jewelry-quality diamonds, with a mass of 97.92 and 85.62 carats, respectively, are very rare, according to officials from Alrosa, the Russian diamond mining group whose miners made the incredible find.
In a press release, Alrosa sales director Yevgeny Agureyev confirmed that large stones of more than 50 carats are "extremely rare," and traditionally sold at auction, where they command high prices. The rarest and cleanest of them are refined by Alrosa's diamond division and sold by the company independently.
Alrosa is one of the largest diamond producers in the world, accounting for about 29% of global production, with mining operations in Yakutia and Arkhangelsk Region. In 2017, the company reported a 6% increase in its diamond output to 39.6 million carats.