CU-1C-1966-08 Cud
Error
Description
Designated CU-1C-1966-08, this eighth documented cud variety for the 1966 Lincoln cent provides further evidence of the toll that sustained high-volume production took on the Philadelphia Mint's die inventory. When a business strike die produces coins, each impression subjects the die steel to compressive forces exceeding 40 tons concentrated over the small 19mm diameter of the cent. The rim area absorbs disproportionate stress because the die collar confines the metal flow during striking, creating a zone of intense pressure at the die's periphery where the cavity meets the collar wall. Over hundreds of thousands of strikes, this peripheral stress nucleates microscopic cracks that gradually propagate through the die steel. When a crack reaches critical length, the affected section of rim separates abruptly, producing the die failure that creates a cud on subsequently struck coins. The 1966 cent production of 2,188,147,783 business strikes required an estimated four to five thousand die pairs over the course of the year, and the extended service lives demanded by the Mint's production targets ensured that a meaningful fraction of those dies reached the fatigue threshold where rim fractures become probable. Cross-referenced as CU-1C-1966-08 and attributed by Cuds on Coins. The 1966 date carries no mint mark under the Coinage Act of 1965, which had removed all mint marks from U.S. coinage beginning the previous year. Struck on a 3.11-gram, 19mm planchet of 95% copper and 5% zinc.
Attribution History
- Discovered by Chuck Newman
- CU-1C-1966-08
- Expert attribution by Cuds on Coins
External References
Community & Reference
Related Errors
More Cud Errors
Collector Essentials
Tools for examining and preserving error coins and die varieties.
10x-20x Jeweler's Loupe
Essential for examining die varieties, doubled dies, and RPMs
Cherry Picker's Guide
The definitive reference for U.S. error coins and die varieties
2x2 Coin Flips & Holders
Protect and organize your finds with archival-quality holders
USB Digital Microscope
Capture detailed images for documentation and community submissions
As an Amazon Associate, NumisDex earns from qualifying purchases.









