Bought this off a forum member a few months ago. Unfortunately I failed to notice the ring of discoloration around the caseback medallion (was so focused on the enamel itself). Has anyone seen this before? Is it actually corrosion? Do you think it can be removed?
That ring has become discolored, but I don't know if it's corrosion. You're in the best position to determine that. IMO, generally it's best just to accept cosmetic aging and not try to clean everything up to make it look new. The medallion itself looks great.
I think it could also be residue of the protective laquer originally applied. Here are pictures I took when the watch still was mine
Interesting. At any rate, I'm by no means definitely going to try and remove it, was just curious. I suppose if it was lacquer it could technically be removed. The dial's where the action is at