1970-S Doubled Die Reverse WDDR-001

Description

Holding the distinction of being the first cataloged doubled die reverse for the 1970-S proof Kennedy half dollar, WDDR-001 occupies the primary position in the Wexler Team's DDR census for the final year of 40% silver-clad proof half dollar production. Cross-referenced as Wexler Variety ID 1970-S 50¢ Pr WDDR-001, this variety was discovered on a proof specimen from the 2,632,810 proof sets produced by the San Francisco Mint that year. No die markers were noted for either the obverse or reverse, meaning attribution relies primarily on matching the doubling pattern to the Wexler Team's published photographs and diagnostic descriptions. The 1970-S proof half dollar holds particular significance in the Kennedy series because it was the last year proofs were struck in the 40% silver-clad composition (outer layers of 80% silver / 20% copper bonded to an inner core of 79.1% copper / 20.9% silver) before the transition to copper-nickel clad proofs beginning in 1971. This composition change makes 1965-1970 proof Kennedy halves a distinct subset within the series, and doubled die varieties on these silver-clad proofs carry the dual appeal of variety attribution and silver content. Proof die manufacturing at San Francisco involved meticulous hub-to-die transfer processes designed to produce the mirror-finish surfaces that characterize proof coinage, yet the same multi-step hubbing procedure that created those lustrous fields also generated the occasional misalignment that produced varieties like WDDR-001. As the -001 designation in the catalog, this variety establishes the baseline against which all subsequent 1970-S proof DDR discoveries are numbered and compared.

Attribution History

• Wexler Variety ID: 1970-S 50¢ Pr WDDR-001
• Expert attribution by Wexler Team

External References