In metalworking, the heating of a metal to soften it and then working it by hammering. It is a process used for the working of iron and steel after smelting. Though copper and other metals can be worked cold with occasional annealing this is not a suitable procedure for iron and steel. Forging involves the heating of the bloom to red heat and hammering. This would be carried out on a flat anvil with a hammer to remove impurities and the remains of slag. The resulting bars of iron could then be thinned down and hammered into shape again continuously heating the iron and hammering while red-hot. During the forging process iron can be bent flanges or other features introduced or sheet metal produced.