Rio Tinto is a global diversified miner. Iron ore is its major commodity, with lesser contributions from copper and aluminum. Lithium, diamonds, gold, and industrial minerals are more minor contributors. The 1995 merger of RTZ and CRA, via a dual-listed structure, created the present-day company. The two operate as a single business entity, with shareholders in each company having equivalent economic and voting rights. Major assets included the Pilbara iron ore operations, a 30% stake in the Escondida copper mine, 66%-ownership of the Oyu Tolgoi copper mine in Mongolia, the Weipa and Gove bauxite mines in Australia, and six hydro-powered aluminum smelters in Canada.