I am not pretending to be an expert on this matter at all but i would assume that you would want a different polish considering the guitar is wood and the trumpet is brass, i would guess you would use some sort of brass polish like the sort of stuff you would use to clean candlesticks or other things that are brass
Bones, sinking like stones.
^Yeah, it looks funky when you use it on metal... don't do it. Buy some brass finish, it's cheap.
Looking for my India/Django.
I wouldn't even polish it at all. Yellow brass (I'm assuming you got a student trumpet, if you don't know what kind of brass it is, it's yellow) doesn't need it, and you're more likely to get the **** somewhere that it will affect your playing than you are to do anything to improve the instrument.
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