From the era of beatniks and hula hoops comes this four-Proof set collection that includes the 1956, 1957, 1958 and 1959 U.S. Proof sets — 20 coins in all. Every one of the silver coins were struck in 90% fine silver. Each Proof set includes a Franklin Half Dollar, which hasn’t been struck in over 40 years. This four-set collection comes in U.S. Mint packaging and a black case that holds up to 20 Proof sets.