Hello, recently I purchase a coin with some green patina near the edge to the rim. I am going to send these coin to NGC for grading, my question is should I clean that little spot first or leave it alone. I am concern about NGC will not grade the coin with green patina on it, or if I clean it, they will know that I have clean it and return the coin to me..
It appears to be a copper coin and that sure looks like verdigris to me. It needs to be removed or it will eventually damage the coin - if it hasn't already. But rather than trying to remove it yourself and you think the coin is worth the cost of slabbing - then I would suggest having NCS remove it for you. And then - if the coin CAN be slabbed, if it is damaged already NGC will not slab it - NCS can give the coin the NGC for slabbing. One other option is to have NCS slab the coin for you - but they will not grade it.
Probably they won't grade it in either case. But we've all been surprised before by what the grading services slab and what they don't. That's true for all grading services, not just NGC.
