United States Mint and Proof Sets
Beginning in 1936, the US Mint began offering sets of Proof and Mint State coins. Proof sets were created for numismatic purposes, while Mint sets consist of Uncirculated specimens of each coin for that year. Special Mint Sets were also available, with coins having a proof-like appearance. Prestige Proof Sets were offered from 1983 until 1997, and included a Silver commemorative dollar.