Those lines look like the residue of flowing liquid on a dirty surface to me. It does not look like typical corrosion to me. If you dip or rinse it in water I bet some of it comes off.
Looks to be encased in a hard plastic case. No matter as the lines on the coin are fluid flow lines and they are they to stay. The coin was dipped or immersed in a fluid and it was not rinsed properly. This is the result.
I can't find "corriiison" in the Oxford dictionary or any others so am not sure how to answer the question. It looks like your camera is on LSD or something like that.