How much is a copper dime 1911 worth?

There's no such thing as a copper dime. All 1911 dimes (in fact all dimes up till 1964) were made of a 90%-silver alloy.

It's quite possible your coin is simply an ordinary silver dime with a lot of tarnish. If so, don't try to clean it; that'll reduce its value to a collector.

There's more information at the Related Question.