(1964-65) Quarter Pattern - RB-3210, INCO

Coin Details

Description

An INCO experimental Washington Quarter designated RB-3210, the middle entry in the three-piece RB-32xx sub-group that constitutes the final alloy family in the Reed-Brenner catalog of 1964-65 clad coinage test strikes. This piece occupies a position of singular numismatic importance as one of the last experimental compositions produced in what was arguably the most consequential metals research program in American coinage history. The RB-32xx sub-group, with only three known compositions, represents the most compact alloy family in the entire INCO program — a marked contrast to the sixteen-composition RB-25xx sub-series that preceded it. This compression indicates that the RB-32xx experiments were highly targeted, testing specific compositional hypotheses rather than conducting the broad parametric surveys that characterized earlier testing phases. The ten-unit spacing between entries (RB-3200, RB-3210, RB-3220) may indicate that the parameter being varied could only take a limited range of values, or that the composition space being explored was narrow enough that three data points provided sufficient coverage. RB-3210 stands at the center of this final investigation, its physical properties embodying one of the last questions that INCO's metallurgists needed to answer before their program could be declared complete.

Rarity Notes

Extremely rare. Population estimated at 1-3 specimens. One of the final three compositions tested in the entire INCO experimental program.

Cross References

RB-3210 (Reed-Brenner), NGC ID: 61914