c.1964 Quarter Pattern - P-5393, DuPont

Coin Details

Description

The third known experimental quarter composition from DuPont's unsuccessful bid for the clad coinage contract, representing yet another alloy formulation in the company's systematic exploration of silver-replacement technologies. P-5393 differs from its companions P-5389 and P-5391 in metallic composition, though all three share the Washington quarter format. Together, these three DuPont patterns provide a cross-section of the company's approach to the clad coinage problem, each optimizing a different combination of physical properties — hardness, ductility, corrosion resistance, color, and electromagnetic signature. The Treasury Department's selection process in 1964-1965 involved extensive testing of candidate alloys not only at the Philadelphia Mint but also by the National Bureau of Standards and by vending machine industry consultants, who subjected sample coins to thousands of machine cycles to verify acceptance rates. DuPont's compositions, while technically sophisticated, did not achieve the same level of electromagnetic compatibility with existing silver-coin detectors that INCO's copper-nickel clad sandwich provided. These patterns are among the most historically significant modern U.S. experimental coins, documenting the industry-wide competition that shaped American coinage for the next sixty years and beyond.

Rarity Notes

R-8+ (Extremely Rare to Unique). The rarest of the DuPont experimental quarter series, with only 1-3 specimens known.

Cross References

Pollock P-5393. Part of the DuPont experimental clad coinage series (P-5389, P-5391, P-5393).