Webster's 1828 entry for "brass" defines it as "an alloy of copper and zink."
Noah Webster, 1828 Webster's Dictionary, (The Editorium, 1828), "Brass," accessed January 20, 2023
BR'ASS, noun
1. An alloy of copper and zink, of a yellow color; usually containing about one third of its weight of zink, but the proportions are variable. The best brass is made by cementation of calamine or the oxyd of zink with granulated copper.
2. Impudence; a brazen face.