my favorite coin i have is an 1834 capped bust half. i also like my 1934-S Peace dollar and my 1878-S Morgan
They can't touch WingedLiberty,s matte proofs, but 1917 Lincolns have the most detail I have seen on Lincolns.
It's hard to decide on just one. I really like the design of Morgan dollars. I also really like Franklin halves and standing liberty quarters though. Oh, and walker halves.
If you exclude commemoratives and insist on it being a coin I actually own, I guess my favorite is my 2005W 1/10 oz gold proof eagle, partly for sentimental reasons (it was a very unexpected gift, and the first gold coin I ever owned). Among coins I bought for myself, I'd say my 1877-S Trade dollar (AU details, chopmarked) just because I love the history you can sense in it. A close runner up would be my somewhat damaged 1835 capped bust half, for the same reason. If you're going by an entire series, it would be my JFK halves, because that's the coin series that first got me excited and interested in coin collecting (that, and Lincoln cents, which my grandmother got me started in collecting, and when I first actively started collecting). If you don't insist I actually own it, I'd have to say the St. Gaudens double eagle. I know that's a cliched answer lol, but hey, there's a reason it's a cliche. Just look at it.
Type 1 standing liberty quarter is probably my favorite followed very closely by the 2.5 and 5 dollar gold Indian. But man so many other great choices like walking liberty halves, buffalo nickels and Saint Gaudens to wrap out a top five.
Liberty Nickels. Would love a full set with full kernels on the bottom left ear of corn... those are tough.
All of my favorite coins are low grade also - picture is bad on the second but it shows the detail that is left.
There are a few patterns with this but other then them I know of no other American coin that also is currency of another country. That totally fascinates me This is Judd 656 and no I don't own one of these (yet!)
One of my favorites is the 1794 flowing hair silver/copper dollar. One sold at auction for a cool 10 million.