1964 Quarter Pattern - RB-2565, INCO

Coin Details

Description

Penultimate entry in the RB-2xxx family of INCO experimental Washington Quarters, cataloged as RB-2565 in the Reed-Brenner classification system. This test strike was produced during the final stage of the International Nickel Company's 1964 clad coinage composition research program, only one increment away from the series' conclusion at RB-2575. The position of RB-2565 near the end of the most comprehensive alloy testing program in American coinage history gives it particular significance for researchers studying the development of clad coinage. By the time this composition was being evaluated, INCO had tested approximately sixty documented formulations across the RB-2xxx family alone (spanning three sub-series: RB-22xx, RB-23xx, and RB-25xx), in addition to the compositions cataloged in the RB-1xxx and RB-3xxx families. This massive body of experimental data — unprecedented in the history of coinage metals research — ensured that the composition ultimately recommended to Congress had been thoroughly validated against every conceivable failure mode. The surviving INCO test pieces, including RB-2565, constitute the physical archive of this research program, each specimen embodying the specific metallurgical properties of one candidate composition.

Rarity Notes

Extremely rare. Population be 1-3 specimens. As the penultimate composition in the RB-2xxx family, this piece is among the most difficult INCO quarters to locate.

Cross References

RB-2565 (Reed-Brenner), NGC ID: 61900