Coal is a reliable and affordable energy source. It has been a vital energy source since the Industrial Revolution of the 1800s. As of 2010, coal is the most commonly used fuel for generating electricity around the world. It is also an important ingredient in the manufacturing industry.
The carbon is in the form of coke, providing both fuel for the huge amount of heat at the high temperature needed, and the carbon necessary to separate chemically the iron from the iron-oxide which is the ore itself.
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