Alloy steel is a mixture of iron ore, chromium, silicon, nickel, carbon and manganese, and it is one of the most versatile metals around. There are 57 types of alloy steel, each with properties based on the percentage amount of each element mixed into the alloy. Since the 1960s, electric furnaces and basic oxygen furnaces have been the standard forms of industrial alloy steel production, while other methods have become outdated. The technology of steel production and the quality of output have advanced, but the actual steps to manufacturing alloy steel have not changed and are rather simple to understand.