Here is a picture of what I mean. This is the front/back trim pieces and on this one I noticed flaking around the screw hole. Its sure possible the screw over the years helped to get it to this point, but I noticed it getting a lot worse (to the point of what we see) through some buffing with a cloth and metal polish.

Interestingly enough I tried the magnet test (did not even think to try that before) with a new magnetic shop hook I recently got. It stuck really well, so definitely steel or pot metal.

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