'Iron' in the Bible

Am I as strong as a rock? Am I some kind of iron man?

using an iron stylus with lead for ink! Then they'd be engraved in rock forever.

Though he dodges an iron weapon, a bronze arrow will pierce him.

Iron is taken from the ground; and copper is smelted from ore.

His bones are conduits of bronze; his strong bones are like bars of iron.

He regards iron like straw, and hardened bronze like a dead tree.