Crucible steel is a term that applies to steel made by two different methods in the modern era, although it has been produced in varying locales throughout history. It is made by melting iron and other materials in a crucible and pouring the molten metal into a mould. Crucible steel was produced in South and Central Asia during the medieval era. Techniques for production of high quality steel were developed by Benjamin Huntsman in England in the 18th century; however, Huntsman's process used iron and steel as raw materials rather than direct conversion from cast iron as in the Bessemer process. The homogeneous crystal structure of this cast steel improved its strength and hardness compared to preceding forms of steel.