Ok shame on me for not paying close attention - but here is my story: I attended a coin show and purchased (2) 1921 Merc dimes. 1 was a 21-D the other supposedly a 21-P. I need both for my set. I found a dealer that was willing to negotiate and ended up purchasing both dimes for $94. When I got home and filled in the info on my catalog, I looked closer at the 21 philly. I hadn't noticed, but it really was a 21-D. The mint mark is obvious. I went back to the show and told the dealer what had happened. He said thanks for the honesty and told me to keep the 21-D if I wanted. I did. Here are some pics of the coins. Neither is in high grade, but I am ok with that. The one I thought was a philly has a scratch from "In God We Trust" through the neck. Let me know how you think these will grade Freddypm