Out of all possible emerald sources in Russia, the mine in the Ural mountains produces the most. They were officially discovered in the early 19th century, though may have been a source of Scythian emeralds mentioned by Pliny (23-79 A.D.) in his Natural History (Sinkankas 1981).
Also notable about the mines, specifically the Malysheva mines, is that they are more highly developed than most gemstone mines. This is because they were used as mines for beryllium during Soviet rule after World War I, and the emeralds and alexandrite were byproducts. The point of the beryllium was to develop Soviet nuclear and defense industries, which meant a lot of money was sunk into making Malysheva productive. These mines are one of the most impressive examples of mining infrastructure in the world.