Ferrous metallurgy involves processes and
alloys based on
iron. It began far back in
prehistory. The earliest surviving
iron artifacts, from the 4th millennium BC in
Egypt, were made from
meteoritic iron-nickel. It is not known when or where the
smelting of iron from
ores began, but by the end of the 2nd millennium BC iron was being produced from
iron ores from China to Africa south of the Sahara. The use of
wrought iron (worked iron) was known by the 1st millennium BC. During the medieval period, means were found in Europe of producing wrought iron from
cast iron (in this context known as
pig iron) using
finery forges. For all these processes,
charcoal was required as fuel.