1966 SMS

The 1966 SMS Roosevelt dime is one of 2,261,583 pieces issued in the Special Mint Set program, the second of three years during which the Treasury substituted SMS coins for traditional proof sets. With proof production still suspended at San Francisco under the coin-shortage emergency directives, SMS coins were struck on polished planchets from polished regular-production dies and packaged in Mint-issued cellophane sleeves within a cardboard holder. The 1966 SMS dimes carry no mintmark in accordance with the 1965-1967 directive, even though San Francisco was the actual production facility. The 1966 program saw modest refinements to the polishing routine that produced slightly more consistent satin surfaces and a higher proportion of cameo-contrast examples than the 1965 release, though the SMS finish remained distinct from the mirrored fields of a true proof.

The 1966 SMS follows the standard clad specifications: 2.268 grams, 17.91 millimeters, outer layers of 75% copper and 25% nickel bonded to a pure copper core, reeded edge. Authentication centers on distinguishing the SMS finish from both circulation strikes and true proofs. The SMS surface shows a satin-to-matte finish from the polished planchet struck on polished dies, distinct from the deeply mirrored fields of a proof and from the cartwheel luster of a circulation strike. Rims are squared and slightly tighter than circulation work but lack the crisp knife-edge definition of proof rims. PCGS and NGC use the "SP" (Specimen) designation, often annotated "SMS" on the label. The 1966 SMS shows slightly better cameo retention than the 1965 due to the refined die-polishing routine, and examples in the original Mint cellophane with strong frost across the FDR portrait and the torch flame carry meaningful premiums in deep-cameo grades.

Survivor distribution covers SP63 through SP68, with SP66 and SP67 the most heavily traded grades. The deep-cameo premium widens sharply at SP67 and above because of the limited supply of strong-contrast survivors. Hairlines from cellophane handling and small carbon spots from long-term storage are the typical impairments below SP65. For broader context, see the Roosevelt Dime series history.