U.S. 1965-1969 Kennedy Half Dollar 5-Coin Silver Set, Brilliant Uncirculated. After 1964, 90% silver coins were discontinued. Beginning in 1965, the only circulation coin struck for commerce with a 40% silver content was the Kennedy half dollar. Just one mint struck these 40% silver issues annually: Philadelphia in 1965-1967 and Denver in 1968-1969. Our set includes all five 40% silver BUs struck for circulation (when silver spiked again in early 1970, the coin appeared only in 1970 U.S. mint sets).