1880 silver dollar city coin with train on the back?

It's not a US coin, it's a privately made "silver round" sold for its metal content. You need to know what purity and weight of silver is in it. On most rounds that information is displayed somewhere within the design; e.g. "1 oz .999 Fine" or similar.

If it doesn't have that information it's probably not real silver, or only silver plate.