You only need 1 thread Looks like a 1943 that was once plated with copper If it sticks to a magnet.. then it's steel I never heard of a 1943 S mint copper Cent
I would say that you have a 1943-S Steel Cent, and that some of the Zinc plating has worn off to expose the steel. Once this happens the steel will start to rust. It looks like someone scraped the edge with a file or something similar near the word Trust.
And here is the same cent notice the reflection of the leaves,,,, it has a very deep blueish white mirror finish,,, and this cent had a strange silver plastic like coating on it after removed a hard shiny surface as you can see, and reverse is equally brilliant,,, this surface is definitely not plating,,,,
Maybe a metal test report to send with it,,,do they grade on condition and or will they look for other things,,, errors, die variables,,what im asking is ,, one grader different from another like specialized on different types of coins
It really looks like someone was messing with it. More than likely, a plating experiment gone bad. Either someone trying to make a fake copper 43 or reconditioning the cent (zinc replate)