I have some brassware with nice engraved designs that I'd like to bring out. If it were silver or gold, I'd use niello, but that apparently doesn't work on brass. I could try and do something to oxidise the whole surface and polish the oxidation off of the high points of the engraving, but ideally I'd like something darker.
I can see from pieces like this:
Engraved lamp stand from the Met Museum, public domain
that such a finish is achievable, but the entry just lists it as
Brass; cast, engraved, and inlaid with black compound
So, what is the equivalent to niello which can be used to selectively darken recessed areas of a brass object?
I'd prefer more traditional methods, as opposed to simply spray painting the whole thing black and rubbing it off the high points, if possible.