"Severalmaz" ("North Diamond") is located in the Archangelsk region. Its operator, "Alrosa", is the largest diamond mining company in Russia.
Way to the richest Lomonosov deposit
Diamonds were found in the Archangelsk region in 1980, the Lomonosov deposit turned out to be the largest in Europe. For 2012 its resources are 220 million carats (1 carat-0,2g), their cost is 12 billion dollars.