Metal and Iron Ore Mining

The Earth’s most important iron ore deposits are found in sedimentary rocks. They formed from chemical reactions that combined iron and oxygen in marine and fresh waters. The two most important minerals in these deposits are iron oxides: hematite (Fe2O3) and magnetite (Fe3O4). These iron ores have been mined to produce almost every iron and steel object that we use today – from paper clips to automobiles to the steel beams in skyscrapers. Ores containing very high quantities of hematite or magnetite (greater than ~60% iron) are known as “natural ore” or “direct shipping ore”, meaning they can be fed directly into iron-making blast furnaces.

Iron (Fe) is one of the most abundant rock-forming elements, constituting about 5% of the Earth’s crust. It is the fourth most abundant element after oxygen, silicon and aluminum and, after aluminum, the most abundant and widely distributed metal. Iron is indispensable to modern civilization and people have been skilled in its use for more than 3,000 years. However, its use only became widespread in the 14th century, when smelting furnaces (the forerunner of blast furnaces) began to replace forges.