It recovered the rare-shaped stone, which experts estimated to be over 300 million years old, on January 23 at the Udachnaya kimberlite pipe in Yakutia.

Alrosa managing board member and director of the United Selling Organisation Evgeny Agureev said diamonds that resemble objects or symbols were "extremely rare in nature", with most either octahedron-shaped or without any particular shape.

"The appearance of a heart-shaped rough diamond, especially on the eve of Valentine's Day, seems to be a symbolic gift of nature not only to our company, but also to all loving couples," he said.

Alrosa apparently has a gift for recovering relevantly-shaped stones, saying it had found a soccer ball-shaped diamond during the 2018 FIFA World Cup and a skull-shaped stone around Halloween.