Coke is a grey, hard, and porous coal-based fuel with a high carbon content and few impurities, made by heating coal or oil in the absence of air—a destructive distillation process. It is an important industrial product, used mainly in iron ore smelting, but also as a fuel in stoves and forges when air pollution is a concern.
Raw coke
The original blast furnaces at Blists Hill, Madeley
Illustration of coal mining and coke burning from 1879
Coal coking ovens at Cokedale, Colorado, supplied steel mills in Pueblo, CO
Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the form of magnetite (Fe3O4, 72.4% Fe), hematite (Fe2O3, 69.9% Fe), goethite (FeO(OH), 62.9% Fe), limonite (FeO(OH)·n(H2O), 55% Fe), or siderite (FeCO3, 48.2% Fe).
Hematite, the main iron ore found in Brazilian mines
Stockpiles of iron ore pellets like this one are used in steel production.
An illustration of iron ore being unloaded at docks in Toledo, Ohio
Banded iron ock, estimated as being 2.1 billion years old