Glossary

Iron ore is a naturally occurring mineral rock from which metallic iron (Fe) can be economically extracted. It serves as the primary raw material for producing iron and steel, which together make up about 95% of all metal used globally. The ore itself is a combination of iron-bearing minerals and impurities such as silica, alumina, and other oxides.

To extract usable iron, the ore must contain a high percentage of iron compounds, typically iron oxides, which can be reduced to pure metallic iron through smelting in a blast furnace or a direct reduction process. The most important iron-bearing minerals are:

- Hematite (Fe₂O₃): Usually red to reddish-brown in color and containing up to 70% iron, hematite is one of the richest and most sought-after iron ores. It is the principal source of iron in many modern steelmaking operations.

- Magnetite (Fe₃O₄): A black, magnetic mineral containing about 72% iron, magnetite is the highest-grade iron ore. It often requires magnetic separation to concentrate the iron before smelting.

- Goethite (FeO(OH)) and Limonite (FeO(OH)·nH₂O): Brownish ores with lower iron content (40–60%) that often form through weathering of other iron minerals.

- Siderite (FeCO₃): An iron carbonate mineral containing around 48% iron, used less commonly because it requires additional processing to remove carbon dioxide.

The process of turning iron ore into usable metal begins with mining, followed by crushing, grinding, and concentration to increase the iron content and remove impurities. The resulting iron ore concentrate or pellets are then fed into a blast furnace, where they are chemically reduced by carbon monoxide (produced from coke) according to reactions such as:

Fe2​O3​+3CO→2Fe+3CO2​

This reduction converts iron oxide into molten pig iron, which can then be refined into steel or cast iron.

Major iron ore deposits are found in Australia, Brazil, China, India, Russia, and the United States, with Australia and Brazil accounting for the majority of global exports. The ore is typically transported as raw rock, concentrate, or pellets to steel mills around the world.