Iron ores are 
minerals from which metallic 
iron can be extracted. The iron itself is usually found in the form of 
magnetite[?] (Fe
3O
4) or 
hematite (Fe
2O
3), 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 minerals such as 
taconite[?], which must be processed to remove non-iron-bearing components prior to 
smelting.  Iron mines therefore produce tremendous amounts of 
waste.
Iron ore is common worldwide, but commercial mining operations are dominated by seven countries:  Australia, Brazil, China, India, Russia, the USA, and the Ukraine.  World production averages one billion metric tons of raw ore annually.
Most iron ore is used in the production of steel.
 
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