Mir mine

The diamond-bearing deposits were discovered on 13 June 1955 by Soviet geologists Yuri Khabardin, Ekaterina Elagina, and Viktor Avdeenko during the large Amakinsky Expedition in Yakut ASSR. There they found traces of the volcanic rock kimberlite, which is usually associated with diamonds. This was the second success in the search for kimberlite in Russia (the first being Zarnitsa mine in 1954), after numerous failed expeditions of the 1940s and 1950s. For his discovery, Khabardin was given in 1957 the Lenin Prize, one of the highest awards in the Soviet Union. == Development ==

The development of the mine started in 1957, in extremely harsh climate conditions. Seven months of winter per year froze the ground, making it hard to mine, and during the brief summer months the ground turned to slush. Buildings had to be raised on piles, so that they would not sink from their warmth melting the permafrost. The main processing plant had to be built on better ground, found away from the mine. The winter temperatures were so low that car tires and steel would shatter and oil would freeze. During the winter, workers used jet engines to thaw and dig out the permafrost or blasted it with dynamite to get access to the underlying kimberlite. The entire mine had to be covered at night to prevent the machinery from freezing. ==Operations==

In the 1960s the mine was producing of diamond per year, of which a relatively high fraction (20%) were of gem quality. The Mir mine's surface operation lasted 44 years, finally closing in June 2001. Later, the mine was operated by Alrosa, the largest diamond producing company in Russia, and employed 3,600 workers. It had long been anticipated that the recovery of diamonds by conventional surface mining would end. Therefore in the 1970s construction of a network of tunnels for underground diamond recovery began, and by 1999 the project operated exclusively as an underground mine. In order to stabilize the abandoned surface main pit, its bottom was covered by a rubble layer thick. and the Mir mine closed in 2004. The mine was recommissioned in 2009, and is expected to remain operational for 50 more years. ==Mir's largest diamonds==

The then-largest diamond of the mine was found on 23 December 1980; it weighed and was named "26th Congress of the Communist Party of the Soviet Union" (). In 2025, Alrosa announced the discovery of the largest diamond mined in Russia, a 468-carat piece named "80 Years of Victory in the Great Patriotic War" that was dug from the mine. ==See also==