Wrought Iron
Wrought iron is a very pure form of commercial iron, having a very small carbon content. It is tough, malleable, ductile and can be easily welded. However, it is too soft to make blades and swords. When formed into bars, it is known as "bar iron". more...
Wrought iron has been used for thousands of years, and represents the "iron" that is referred to throughout history.
Wrought iron was originally produced by a variety of methods today known as a bloomery. Bloomeries used charcoal-heated smelters, typically in the form of small pots or ladles, into which the ore was poured and then covered with a thin layer of charcoal. Air was blown onto the charcoal after lighting it on fire. The heat produced would melt the ore. As the ore melted it would be reduced (ore is iron oxide, or rust), mixing with the charcoal to release carbon dioxide. This way little carbon entered the iron directly.
In a bloomery, the fire does not get hot enough to melt the iron completely, so you are left with a spongy mass containing iron and silicates from the ore; this is iron bloom from which the technique gets its name. The bloom was then mechanically worked to break off the masses of slag and impurities. This process gives rise to the name "wrought", as the iron was pounded, twisted, and folded. As a result of this process, many strands of slag are mixed into the metal. These slag inclusions give it a "grain" like wood, and distinct look when etched. Also due to the slag, it has a fibrous look when broken or bent past its failure point.
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