cleaning brass with what?

[Ceannt]

Braso and elbow grees

[Matt Lukes]

Real questions is:did the Roman metalsmiths clean brass/bronze between annealing? I don't think I've seen anything on that.

That's probably WAY to general a question- since there were probably thousands and thousands of metalsmiths who had lots of different methods and techniques. It could also depend on the type of thing being made- if you're doing intricate repousse/chasing it definitely helps to remove the crud so you can clearly see where you need to work next. On something simpler maybe there's no reason.