Iron Ore
noun
てっこう
鉱物 （こうぶつ） Mineral
鉱石 （こうせき） Ore, Mineral
鉄鉱 （てっこう） Iron Ore
鋼鉄 （こうてつ、not on WK） Steel
Iron is an element while steel is an alloy comprised of iron and carbon. Steel is man made, so you won't find it in nature. You won't find steel in ore, only iron which can be manufactured into steel.