Looks like 1920 from that last photo, and like there might be a mintmark from the middle photo. I'd do a vinegar soak. With that condition and those gouges on the back, it's not like there's any value left to be reduced.
I agree with Jeff. The ribbon indicates a 1920's Buffalo Nickel. You may be able to narrow it down to which year, but the mint mark, if there is one, looks to be too far worn. Jim makes a good suggestion: you may be able to do some sleuthing to see if there is any relief to find. Or angled lighting might work too.
I'm guessing 1921. The ribbon on the 1920 and 1921 are similar, but the gap between the inside of the ribbon and the hair/ribbon is narrower on the 1921. That appears to be the case here. However, the hair detail above the tied ribbon looks like a worn 1920. If you pickle that nickel, you will know for sure, but 'ruin' the coin. If you leave it alone and can gather consensus, you might dial in on a date and preserve the coin.
Didn't even think about that.So possible buffalo date ranges can be used by details just like attributing large cents.
Thing is, I just thought I saw the top three-quarters of a digit "2" followed by most of a digit "0". Today was my day to learn about the die markers you just posted. Thanks!
I think I see what you are seeing...and the three divots above the tie of the ribbon would seem to confirm the 1920 attribution. No need to pickle the nickel.
Not that it makes any difference, but I see 1920 also. When I've gotten rolls of undated Buffalo nickels, and brought the dates up, 1920 was the most common. In any case, the nickel has no collector value, so whatever you do with it doesn't really matter, IMO.
I have some undated buffalo nickels I found while roll searching. I threw them in with my wheat penny can.