Group of 2 United States Mint Proof Sets 1971-1972. 10 coins. Group of 2 United States Proof Sets 1971-1972 10 coins. Each Set contains 5 Proof Coins, the Kennedy Half, Washington Quarter, Roosevelt Dime, Jefferson Nickel, and Lincoln Cent. Each coin was struck at the San Francisco Mint and carried the “S” mint mark. The groups of five coins were placed in a rigid plastic holder with the coins held in place by a black plastic insert, the holder was placed into a blue cardboard box. Some 1971 Proof Sets contain the 1971 “No S” Proof Jefferson Nickel, trend pr69DCAM $3650. These has not been check. An estimated 1,655 of the “No S” coin were produced. Some coins may be encountered with a cameo or deep cameo finish.