Editing Blacksmith (section)

== Terminology ==
[[File:Blacksmith working.jpg|thumb|Hot metal work from a blacksmith]]
* [[Iron]] is a naturally occurring metallic element. It is almost never found in its native form (pure iron) in nature. It is usually found as an [[oxide]] or [[sulfide]], with many other impurity elements mixed in.
* [[Wrought iron]] is the purest form of iron generally encountered or produced in quantity. It may contain as little as 0.04% [[carbon]] (by weight). From its traditional method of manufacture, wrought iron has a fibrous internal texture. Quality wrought-iron blacksmithing takes the direction of these fibers into account during forging, since the strength of the material is stronger in line with the grain than across the grain. Most of the remaining impurities from the initial smelting become concentrated in silicate [[slag]] trapped between the iron fibers. This slag produces a lucky side effect during forge-welding. When the silicate melts, it makes wrought iron self-fluxing. The slag becomes a liquid glass that covers the exposed surfaces of the wrought iron, preventing oxidation which would otherwise interfere with the successful welding process.
* [[Steel]] is an alloy of iron and between 0.3% and 1.7% carbon by weight. The presence of carbon allows steel to assume one of several different crystalline configurations. Macroscopically, this is seen as the ability to "turn the hardness of a piece of steel on and off" through various processes of heat-treatment. If the concentration of carbon is held constant, this is a reversible process. Steel with a higher carbon percentage may be brought to a higher state of maximum hardness.<ref name=metalsHandbook>{{cite book|last=Davis|first=J.R.|title=Metals Handbook, 2nd Ed.|year=1998|publisher=ASM International|location=Materials Park, OH|isbn=0-87170-654-7|url-access=registration|url=https://archive.org/details/metalshandbook00davi}}</ref>
* [[Cast iron]] is iron that contains between 2.0% to 6% carbon by weight. There is so much carbon present that the hardness cannot be switched off. Hence, cast iron is a brittle metal, which can break like glass. Cast iron cannot be forged without special heat treatment to convert it to [[malleable iron]].<ref name=metalsHandbook />

Steel with less than 0.6% carbon content cannot be hardened enough by simple heat-treatment to make useful hardened-steel tools. Hence, in what follows, wrought-iron, low-carbon-steel, and other soft unhardenable iron varieties are referred to indiscriminately as just ''iron''.