A finery forge is a hearth used to fine (i.e., produce, refine) wrought iron, through the decarburization of the pig iron. The fining process involved liquifying cast iron in a fining hearth and removing carbon from the molten cast iron through oxidation. Finery forges were used as early as 3rd century BC, based on archaeological evidence found at a site in Tieshengguo, China. The finery forge process was replaced by puddling process and the roller mill, both developed by Henry Cort in 1783-4, but not becoming widespread until after 1800.