Iron is a common metal found in the earth's crust, where it occurs in combination with other elements. The term "iron ore" is used when the rock is sufficiently rich in iron minerals to be mined economically. Iron ore yields metallic iron (Fe) when heated in the presence of a reducing agent such as coke. Iron ore usually consists of iron oxides and carbonates.
Its most important mineral forms are magnetite (Fe3O4, 72.4% Fe), hematite (Fe2O3, 69.9% Fe) and siderite (FeCO3, 48.29% Fe). In Brazil, some ore that contains practically no other minerals can grade as high as 68% Fe, but the crude ore mined in Canada grades between 30 and 44% Fe. Therefore, these mines crush and grind the ore, then use gravitational and magnetic concentration methods to produce concentrates with an iron content of about 65%. Depending on grain size, the concentrate is then shipped as is, or agglomerated into balls about a centimetre in diameter and fired to produce hard iron ore pellets. Steel companies take the pellets and coke made from coal and load them into blast furnaces, where the minerals are reduced to metallic iron. Unpelletized concentrate received at steel plants is sintered before being charged to the blast furnace.
Iron ore, along with copper and coal, was one of the first mineral resources mined in Canada. The smelting and casting of iron was Canada's first industry. Before European settlements were established, there is evidence of Inuit exploitation of iron meteorites for metal. In the 13th century at the Viking settlement at L'Anse aux Meadows, local bog iron was roasted and wrought to make nails for ships. In about 1670, deposits of bog iron were found near Trois-Rivières, Qué, and by the 1740s Les Forges Saint-Maurice was producing top-quality cast iron stoves, pots, kettles, bullets and cannons. Today, steel manufacturing is one of Canada's few major industries that are largely Canadian owned. There are iron ore producers in Newfoundland, Québec and BC.
Canada produces approximately 35 million tonnes of iron ore annually. Countries that Canada exports to include Germany, UK, US, Japan, China, South Korea and the Philippines.
See also Iron and Steel Industry.