Deut 8:9 — KJV renders Hebrew nechosheth as 'brass' ('out of whose hills thou mayest dig brass'), while NRSVUE and NIV render it 'copper', implying the KJV made a metallurgical/translation error.

Concede the point honestly, but locate it correctly: this is a documented shift in English word-sense, not an error in reading the Hebrew. נְחֹשֶׁת (nechosheth) denotes copper or copper-based alloys generically. In 1611 English, 'brass' was used loosely for copper and copper alloys alike (compare the KJV's 'brazen serpent' and 'brazen altar', both referring to bronze/copper objects) — a broader semantic range than the modern, narrower sense of 'brass' as a copper-zinc alloy. This is a known instance of lexical semantic narrowing in the history of English, not evidence the KJV translators misunderstood the underlying Hebrew geology. Archaeological work at sites such as Timna and Faynan has since confirmed Iron Age copper mining exactly in the region Deuteronomy describes, which is precisely the kind of comparative and archaeological data 1611 translators lacked. Modern translations correct the English gloss using improved metallurgical and archaeological knowledge — a routine act of lexicography, not a discovery that the underlying Hebrew text is unstable.

The underlying Hebrew consonantal text (נְחֹשֶׁת) is stable across the manuscript tradition; only the English gloss changed as archaeological knowledge of ANE metallurgy (e.g., the Timna and Faynan copper-mining complexes) improved. Self-correction in translation vocabulary, without any change to the source text, is evidence of translational and textual integrity working as intended.