I've used brass powder for inlays. I used the powder to fill the groove that I had turned away with a parting tool. I put drops of CA on the powder as I worked my way around the groove. After turning it down again and sanding I gave it several coats of all over CA finish. There is a good tutorial in the library. No tarnish yet and I don't see how it can since it is buried deep under CA.
Not brass powder but is it brass: I have used self turned brass rings from .5 and 1 mm brass sheets between segments, and I use a good layer of your CA! Does well. My oldest one like this is 8 months old and no problem so far. I also glued them up with medium CA, so the brass is well coated with CA.