Steel is made from iron, which is usually mined in the form of iron ore. The ore needs to be smelted in order to extract the iron. Smelting is done in a blast furnace, where coke and limestone are added to the iron ore. This mixture is heated to a very high temperature and air is blown through it. The molten iron is drawn off.
To make steel, iron is mixed with carbon and other metals to give it extra harness. There is about 1.6 percent carbon in most steel. Other forms of steel contain elements such as chromium and nickel to prevent rusting. Ordinary carbon steel rusts as easily as iron, and must be protected with paint or other coatings.
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