Grant Hardy discusses 1 Nephi 4:9; claims that the Book of Mormon follows the KJV's anachronistic usage of referring to bronze as "steel" or "brass."
Grant Hardy, The Annotated Book of Mormon (Oxford: Oxford University Press, 2023), 22
9: It is perhaps ominous that Nephi’s attention is first drawn to the sword. Steel, bronze; the BoM follows the anachronistic usage of the KJV in referring to bronze as “steel” or “brass” (2 Sam. 22.35; Job 20.24; Ps 18.34; Jer 15.12; see 2 Ne 3.2n).