(1964-65) Blank Pattern - RB-5390, INCO
Strike Type
Coin Details
Description
Quarter-sized experimental blank planchet RB-5390 from the INCO silver replacement evaluation. This composition marks the last closely spaced entry before the larger numerical gap to RB-5400, indicating it represents the final composition in a continuous subseries. The systematic catalog structure of the INCO experimental program mirrors the scientific rigor that characterized the International Nickel Company's approach to industrial metallurgy. Founded in 1902 through the merger of several Canadian nickel mining companies, INCO had grown into one of the world's most influential metals corporations by the 1960s, with a research capability that rivaled major universities. The company's ability to formulate, produce, and test dozens of candidate alloys in a compressed timeframe was a direct consequence of this institutional depth. RB-5390 embodies one moment in that intensive effort — a specific alloy formulation, produced as a physical blank, evaluated against stringent criteria, and preserved as a record of the process that ultimately transformed American coinage.
Rarity Notes
R-7 to R-8. Very rare experimental blank, produced in quantities of only a few specimens.
Cross References
RB-5390 (Robinson-Breen catalog). INCO experimental blank planchet series, quarter-sized, 1964-65.
External References
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