Walking Liberty half dollar
The Walking Liberty half dollar is a silver 50-cent piece or half dollar coin that was issued by the United States Mint from 1916 to 1947; it was designed by Adolph A. Weinman, a well-known sculptor and engraver. In 1915, the new Mint Director, Robert W. Woolley, came to believe that he was not only allowed but required by law to replace coin designs that had been in use for 25 years.
Source: Wikipedia — Walking Liberty half dollar (CC BY-SA 4.0)