40 And there shall be a fourth kingdom, strong as iron, because iron breaks to pieces and shatters all things. And like iron that crushes, it shall break and crush all these.
Daniel 7
7 After this I saw in the night visions, and behold, a fourth beast, terrifying and dreadful and exceedingly strong. It had great iron teeth; it devoured and broke in pieces and stamped what was left with its feet. It was different from all the beasts that were before it, and it had ten horns.