Rio Tinto is a global diversified miner. Iron ore is the dominant commodity, with significantly lesser contributions from copper, aluminum, diamonds, gold, and industrial minerals. 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.