(in Russian, uklad), crude steel obtained from bloom. Russian chronicles of the 16th century mention Novgorod, Tikhvin, Karelian, and other natural steels.

To produce natural steel, bloom was heated in incandescent coals, resulting in surface carburization of the metal; upon cooling of the metal in water or snow, the layer of steel became brittle and was easily detached by a blow. The operation was repeated until the entire bloom was converted into small sheets. The largest sheets were laid in incandescent coals [hence the Russian name, from ukladyvat’, “to lay down”] and heated to the point of welding; the incandescent mass acquired a dense structure.

Silent weapons, helmets, scythes, and other articles were fabricated from natural steels. With the advent of puddling in the late 18th century and the development of mass-production methods of obtaining steel ingots in the second half of the 19th century, natural steel lost its importance.