'Iron' in the Bible

And he shall be their shepherd, ruling them with a rod of iron, just as earthenware jars are broken to pieces; and his power over them shall be like that which I Myself have received from My Father;

She gave birth to a son--a male child, destined before long to rule all nations with an iron scepter. But her child was caught up to God and His throne,

From His mouth there comes a sharp sword with which He will smite the nations; and He will Himself be their Shepherd, ruling them with a scepter of iron; and it is His work to tread the winepress of the fierce anger of God, the Ruler of all.