Pig iron is the
intermediate product of
smelting iron ore. It is the molten iron from the
blast furnace, which is a large and cylinder-shaped furnace charged with iron ore, coke, and limestone.
Charcoal and
anthracite have also been used as fuel. Pig iron has a very high
carbon content, typically 3.5–4.5%, along with silica and other constituents of
dross, which makes it very brittle and not useful directly as a material except for limited applications.