'Iron' in the Bible

He brought forth the people who were therein, and put them under saws, and under iron picks, and under axes of iron, and made them pass through the brick kiln: and he did so to all the cities of the children of Ammon. David and all the people returned to Jerusalem.

But the man who touches them must be armed with iron and the staff of a spear. They shall be utterly burned with fire in their place."