I would have put this in the Error Coin forum, but I put it here because I would like to know the value (or how much you'd spend - only if you collect them) of this coin...
Struck Through Grease doesn't really add value to it, it actually sometimes decreases the value. I would pay the regular price for a 1939 Merc in that grade. I can't give you an exact number, I'm still learning.
