In all cases were the word "steel" occurs in the Authorized Version the true rendering of the Hebrew is "copper." Whether the ancient Hebrews were acquainted with steel is not perfectly certain. It has been inferred from a passage in (Jeremiah 15:12) that the "iron from the north" there spoken of denoted a superior kind of metal, hardened in an unusual manner, like the steel obtained from the Chalybes of the Pontus, the iron smiths of the ancient world. The hardening of iron for cutting instruments was practiced in Pontus, Lydia and Laconia, and you can find more about that here on st-takla.org on other commentaries and dictionary entries. There is, however, a word in hebrew, paldah, which occurs only in (Nahum 2:3) (4) and is there rendered "torches," but which most probably denotes steel or hardened iron, and refers to the flashing scythes of the Assyrian chariots. Steel appears to have been known to the Egyptians. The steel weapons in the tomb of Rameses III., says Wilkinson, are painted blue, the bronze red.
Main reference: Smith's Bible Dictionary (1860s)
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