1921-S Buffalo? What Do You Make Of This Date...

Not a 1921.

This will be a useful reference image for your project:

Oh, duh! I found an old thread with your post, CaptainFwiffo, but forgot to check for the ribbon wave on this coin/date. I was partway through a sorting round when I saw the post and then starting putting aside 'wavy ribbon' dateless coins into a separate pile so that I could check them against these pictures later.

I'm going to need larger pictures when it comes time for that. I looked at some PCGS pics but with my worn coins the ribbon takes on broader dimensions and looks a little different.

Perhaps it is a 27-S. That's gotta be a 2 and the fourth digit really can't be anything other than a 1 or 7.

I really should get some books and resources. Just downloaded the Kindle edition of Cherrypicker. Got a Rick Snow download too. Several more books are needed, wish they were all available in digital format.

Book recommendations (for all types of US coins 1800's onward) will be appreciated. If the information can readily be found online I don't need it but it is nice to have very detailed info compiled into a book.