@cute, first welcome to CCF. Second, I agree that it isn't an RPM. If it is flat with the surface of the coin, then it is surface staining. If it protrudes up above the surface of the coin then it likely is the zinc core starting to deteriorate. Either way this one is a spender.
"If you climb a good tree, you get a push."
-----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed."
-----King Adz
-----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed."
-----King Adz


























