It just dawned on me the other day after 20 years in the hobby I would not have been able to answer this question. What coin has the first "P" mintmark on a proof??? Have fun!!! Ben Peters
Swag If it is a US coin, then perhaps it is the Birch Cent? Was it struck in specimen proof? There is a "P" in the motto Parent of Science & Industry. Very best regards, collect89 Sorry, you said mint mark. Obviously I must think some more & guess again.