What is the value of an 1871 US silver dollar?

Depending on the mintmark, exact graded condition, and the third party service which graded it, it could range from about $2000 for a Philadelphia-minted coin in MS-60 condition to $50,000 (or even more) for a CC mintmark certified MS-69. With no mint mark on the back, about $250 in average condition.

With a "CC" mint mark, about $3500.

If you have a coin with a CC mint mark, it should be authenticated by a dealer or grading agency to ensure that it's not a counterfeit.