'Iron' in the Bible

Now behold, I have made you today as a fortified city and as a pillar of iron and as walls of bronze against the whole land, to the kings of Judah, to its princes, to its priests and to the people of the land.

All of them are stubbornly rebellious,Going about as a talebearer.They are bronze and iron;They, all of them, are corrupt.

which I commanded your forefathers in the day that I brought them out of the land of Egypt, from the iron furnace, saying, ‘Listen to My voice, and do according to all which I command you; so you shall be My people, and I will be your God,’

“Can anyone smash iron,Iron from the north, or bronze?

The sin of Judah is written down with an iron stylus;With a diamond point it is engraved upon the tablet of their heartAnd on the horns of their altars,

“Go and speak to Hananiah, saying, ‘Thus says the Lord, “You have broken the yokes of wood, but you have made instead of them yokes of iron.”

For thus says the Lord of hosts, the God of Israel, “I have put a yoke of iron on the neck of all these nations, that they may serve Nebuchadnezzar king of Babylon; and they will serve him. And I have also given him the beasts of the field.”’”

“The Lord has made you priest instead of Jehoiada the priest, to be the overseer in the house of the Lord over every madman who prophesies, to put him in the stocks and in the iron collar,