6 Steel, unwrought or semi-wrought; iron, unwrought or semi-wrought; cast iron, unwrought or semi-wrought; common metals, unwrought or semi-wrought; alloys of common metal; ingots of common metal; building materials of metal, namely, soffits; ores of metal, namely, electro-analysis copper ore, electro-analysis lead ore, and electro-analysis nickel ore; aluminium ingot; tinfoil; steel powder; tungsten ore powder; non-ferrous metals, ores and alloys, namely, hafnium, celtium, molybdenum, niobium, tin, bronze, manganese, titanium, vanadium, aluminium, tungsten, cadmium, zirconium, magnesium, cobalt, chromium, tantalum, zinc, chrome ores, silicon iron, ferromanganese, chrome iron, molybdenum iron, steel, cast steel, and tinplate; ducts of metal, for central heating installations; casings of metal for oil wells; railway switches in the nature of metal railway crossovers; iron ores; silver plated tin alloy; white metal; steel alloys; silicomanganese alloys; rails of metal; blooms; tubbing of metal