Do not try to polish them with metal polish, bar keepers friend, etc.
This will remove the clear finish.
When I built my amp and hap the top panel professionally polished I asked how best to remove smudges and finger prints.
To my amazement:
It works great
Further, It's unlikely to be oxidation since it is clear coated.
EDIT: I can't type/spell
Edited by sceleratus - 12/8/13 at 8:30pm