(1964-65) Blank Pattern - RB-5345, INCO
Strike Type
Coin Details
Description
INCO experimental quarter-sized blank RB-5345, yet another data point in the intensive compositional study that characterizes the mid-range of the RB-53xx series. The progression through these closely spaced catalog numbers documents a level of metallurgical rigor that is rarely visible in numismatic form — each blank is essentially a laboratory specimen that happens to have the dimensions of a quarter dollar. The 1964-65 dating reflects the period over which INCO prepared and delivered experimental planchets to the Treasury, a timeline that overlapped with the congressional debate over the Coinage Act of 1965. The political pressure to resolve the silver crisis quickly added urgency to the technical evaluation program, as Treasury officials needed to present Congress with a confident recommendation for a specific alloy composition. Blanks like RB-5345 were part of the evidentiary basis for that recommendation, providing physical proof that practical alternatives to silver existed and could be manufactured at the scale required for national coinage production.
Rarity Notes
R-7 to R-8. Rare surviving specimen from INCO's intensive composition evaluation series.
Cross References
RB-5345 (Robinson-Breen catalog). INCO experimental blank planchet series, quarter-sized, 1964-65.
External References
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