Pearl Drum Badges from all Years/Series.......

[nevDRUM]

Any one here know what type of marks these might be? Could brass cleaner remove it?

[gyorpb]

Common on signature snares. I believe they are lacquered, but the still „rot“, underneath. I‘ve not attempted cleaning mine, but I would probably think along the same lines as you: remove them from the shell, remove the lacquer, hopefully without removing the black fill-in, but that could fairly easily be restored (model paint?). Then brass polish, and a light dusting of clear spray lacquer to seal them, again.