The Walking Liberty half dollar was a silver 50-cent piece or half dollar coin issued by the United States Mint from 1916 to 1947; it was designed by Adolph A. Weinman. Weinman's design of Liberty striding towards the Sun for the half dollar proved difficult to perfect, and Treasury Secretary William G. McAdoo, whose department included the Mint, considered having Barber create his own design. Mint officials were successful in getting Weinman's design into production, although it never struck very well, which may have been a factor in its replacement by the Franklin half dollar beginning in 1948. Nevertheless, art historian Cornelius Vermeule considered the piece to be among the most beautiful US coins. Since 1986, a modification of Weinman's obverse design has been used for the American Silver Eagle, and the half dollar was issued in gold for its centennial in 2016.