the man you want to help you with this is captainwiffo, he is the guy that put together the cheap set of ugly and dateless
Buffalo nickels he taught me how to determine it so let me give it a shot
first you can look at the left ribbon coming out of the indians hair and see that it is wavy and not straight narrowing your coin to 1920, 1921, or 1924 (I am almost 100% sure those are the only dates with the wavy hair ribbon) The ribbon is curved and straight for the other years of
Buffalo nickels. Pick on up another
Buffalo nickel and compare it to the coin you have.
***Note***The ribbon is a little bit more wavy on the 1920 and 1921 then the 1924.
Next thing to look at is detail above the braid where the ribbon comes into the hair. You can see detail shown by hair lines going up into the hair on the 1921 that aren't there on the 1920 or 1924 coins.
Your coin has the wavy left side ribbon and the hair detail above the braid. As far as the mint mark, I see something there. Since in 1921 there was only one coin issued without a mintmark (P) and one coin issued with a mintmark (S) I would have to say that that is an S mintmark.
Thus my conclusion is that you have a 1921 S
Buffalo nickel.
How did I do Captainwiffo?
Congrats on what I believe is a pretty great coin
how did you come across this bad boy