(1965) Half Dollar Pattern - RB-4510, INCO

Coin Details

Description

Experimental clad half dollar RB-4510 from the 1965 INCO testing program, representing a third alloy variant for the Kennedy half dollar denomination. The copper-nickel clad compositions tested on half dollar dies during 1965 were forward-looking experiments, since Congress had already decided that the half dollar would retain 40% silver content in the near term. INCO's decision to test clad compositions on all three denominations simultaneously — dimes, quarters, and half dollars — demonstrated the company's long-range strategic thinking. The data gathered from RB-4510 and its companion pieces would eventually support the Mint's transition of the half dollar to full clad composition beginning in 1971. The Kennedy half dollar's design, with Gilroy Roberts' detailed portrait of President Kennedy on the obverse, provided a particularly demanding test of any new composition's striking characteristics: the fine detail in Kennedy's hair and the presidential seal on the reverse required excellent metal flow properties under coining pressure. RB-4510 was produced at the Medallic Art Company, where the experimental blanks were struck under controlled conditions that replicated production Mint operations as closely as possible.

Rarity Notes

R-7 to R-8. Extremely rare. The mid-series half dollar experiments are scarce even by the standards of the INCO program, which produced limited quantities of all compositions.

Cross References

Research Blank RB-4510 (Gould/INCO experimental series)