Bible Verses About Iron: Of small comparative value

Iron sharpeneth iron; so a man sharpeneth the countenance of his friend.

But hast lifted up thyself against the Lord of heaven; and they have brought the vessels of his house before thee, and thou, and thy lords, thy wives, and thy concubines, have drunk wine in them; and thou hast praised the gods of silver, and gold, of brass, iron, wood, and stone, which see not, nor hear, nor know: and the God in whose hand thy breath is, and whose are all thy ways, hast thou not glorified:

Because I knew that thou art obstinate, and thy neck is an iron sinew, and thy brow brass;

For, behold, I have made thee this day a defenced city, and an iron pillar, and brasen walls against the whole land, against the kings of Judah, against the princes thereof, against the priests thereof, and against the people of the land.

Thy shoes shall be iron and brass; and as thy days, so shall thy strength be.