Iron ores are minerals from which metallic iron can be extracted. The iron itself is usually found in the form of magnetite (Fe3O4) or hematite (Fe2O3), both of which are iron oxides. However, as much of the pure magnetite and hematite ore has already been mined, modern iron mines rely on aggregate ores such as taconite, which must be processed to remove non-iron-bearing components prior to smelting.
Iron ore is common worldwide, but commercial mining operations are dominated by eight countries: Australia, Brazil, China, India, Russia, Ukraine, South Africa and the United States. World production averages one billion metric tons of raw ore annually.
Most iron ore is used in the production of steel.