Instead, the Mint sold Special Mint sets, abbreviated “SMS,” a hybrid of the annual Proof and Uncirculated Mint sets they replaced.
Cased in plastic and offered as five-coin denomination sets, SMS coins were struck from polished dies but lack the typical sharpness and depth of mirror of true Proof coins. Several important Kennedy half dollars are from these offerings.
Cameo contrast coins, struck from fresh dies and exhibiting strong contrast between the fields and design elements, were randomly included in a small number of Special Mint sets.
High-grade Ultra Cameo examples can be worth thousands of dollars today and are among the most valuable of all Kennedy half dollars.
Although no formal explanation exists for its omission, likely overpolishing of a later state die effaced this detail. The coin is unknown with cameo contrast, which supports this late die state hypothesis.
Top of The Line
In 1993, a group of Specimen 1964 coins were offered in a Stack’s auction. These coins were very sharply struck, like Proof coins, from polished dies.
Although their finish was satin rather than brilliant, they were likened to the 1965 through 1967 SMS coins.
They were thought to be either prototypes of the SMS finish or simply special souvenirs of the last 90 percent silver coinage. The sets have been broken up, and coins are available singly.