Green’s Dictionary of Slang

mix-metal n.

[a silversmith’s function]

a silversmith.

1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue.
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.
1895		C. Crowe Aus. Sl. Dict. : Mix Metal, a silver smith.