1921 silver dollar.

The 1921 Morgan dollar is the last year of production for this series, which had ceased in 1904 and was then resumed.  They made millions in each of the three main mints: Philadelphia, Denver, and San Francisco.  The latter two mints can be identified by a D or S Mint Mark located on the reverse under the eagle and the wreath. It's very unpopular with collectors because the dies were regarded as poorly made and it has a very weak appearance to it. Mostly they're worth the value of the silver in them, on a good day about $15.