Lundin Mining has established itself as a mid-tier base metals mining company with a focus in Europe. In June 2004 Lundin Mining acquired a 100% interest in the Zinkgruvan mine from Rio Tinto Plc. The Zinkgruvan mine, which is the largest zink producing mine in Sweden and one of the largest underground mines in Europe, has been in continous production since 1857. In addition, Lundin Mining controls more than 95% of the shares of North Atlantic Natural Resources (NAN), which main asset is the copper-zinc producing mine of Storliden in the Skellefte mining district of northern Sweden. With high grades of both zinc and copper, the mine is one of the lowest cost zinc producers in the world.