What are high value us coins?

Answer 1

That's far too broad a question to answer without writing a small book. The US has issued coins with thousands of different designs, dates, and mint marks over the last 220 years, with denominations ranging from a half-cent to $20.

My suggestion would be to determine what type(s) of coins you're interested in so you can focus more specifically. For instance, are you interested in Morgan dollars? Large cents? Jefferson nickels? and so on.

There are many sites that are good sources of information. I've posted links to 2 of the ones that I've found to be pretty useful for values and rarity.