1968 United States Mint Set in Original Government Packaging With 40% Silver Kennedy. The 1968 Mint Set included a total of ten different coins struck at three different mint facilities. This was comprised of Lincoln Cents (P, D, S), Jefferson Nickels (D, S), Roosevelt Dimes (P, D), Washington Quarters (P, D), and one Kennedy Half Dollar (D). Notably, the half dollar included in the set was struck in a composition of 40% silver. The Philadelphia Mint coins and the single Lincoln Cent struck at the San Francisco Mint were placed within a cellophane pack with a blue stripe and the Denver Mint coins were placed in a pack with a red stripe. The two were placed between sheets of light cardboard within a white envelope marked “1968 U.C.” with the Treasury Department address.