1966 Special Mint Set SMS. In 1964, just when the mint was removing 90% silver coins from circulation, and the us was having a coin shortage, the Mint announced that beginning in 1965, no Proof Sets, or Mint Sets would be produced, Instead they would be making a Special Mint Set. Special Mint Set coins were not proofs, and were not uncirculated, Mint State pieces. Dies for the coins were over polished, while the planchet themselves were not polished. The resulting SMS coins have a brilliant, proof like appearance, much nicer than the run-of-the-mill circulation coins. In 1965 these sets were released in the Traditional Mint Cellophane and White Envelope and in 1966 and 1967 they were packaged in hard, pale blue plastic holders. Note, the set contains a 40% Half Dollar.