well, I can't say for certain from those pictures, but if the mint mark is an S, it's a proof coin which from time to time turn up in circulation. Because it is circulated, it is likely worth less than a nice brilliant proof, but would carry some premium over face to be sure. Oh and just a note: Even a circulated proof coin is a proof coin. Proof is not a condition, it is a method of manufacture. circulated proof coins are generally called diminished proofs.
I hate to say this, but it isn't worth much. If you took it to a dealer, you'd probably get a "not interested," as a response. If you find someone who needs one for their coin book, they might offer you a quarter for it.
