(1965) Half Dollar Pattern - RB-4515, INCO

Coin Details

Description

INCO experimental clad half dollar RB-4515, a fourth composition variant tested on Kennedy half dollar dies during the 1965 second-phase program. This piece continues the systematic evaluation of copper-nickel clad alloys at the half dollar scale, where the physical demands on the composition differ from those of smaller denominations. The half dollar's greater mass means it absorbs more kinetic energy during normal handling, potentially accelerating wear on the outer cladding layers. INCO's testing protocol evaluated each composition's wear resistance through both accelerated laboratory testing — tumbling coins in drum mechanisms that simulated years of pocket circulation — and visual inspection of struck specimens for initial quality. RB-4515 was struck on Kennedy half dollar dies at the Medallic Art Company, bearing the same design that had been enthusiastically received by the American public since the Kennedy half dollar's introduction in 1964. The emotional attachment to this denomination added political complexity to the composition question: Treasury officials needed to balance economic arguments for eliminating silver against public sentiment favoring the retention of precious metal in the coin commemorating President Kennedy.

Rarity Notes

R-7 to R-8. Extremely rare. Most INCO half dollar experimental pieces survive in numbers comparable to the dime experiments, despite the half dollar series containing fewer total compositions.

Cross References

Research Blank RB-4515 (Gould/INCO experimental series)