CU-1C-2021-06R Cud
Error
Description
Sixth reverse cud documented for the 2021 Philadelphia Mint Lincoln Shield Cent, CU-1C-2021-06R rounds out a substantial cluster of die rim failures that invites comparison with earlier production eras. Modern die steel — typically high-chromium tool steel hardened to approximately 58-62 Rockwell C — is engineered for extended die life, yet even contemporary dies eventually succumb to the cumulative stress of striking hundreds of thousands of coins. Six reverse cuds from a single date and mint demonstrates that die rim fractures remain a routine production phenomenon despite metallurgical advances over the past century. Historic die steels were softer and more brittle, producing cuds at higher rates per die pair, but the sheer volume of modern production compensates by generating large absolute numbers of die failures. Cataloged by Cuds on Coins, the 2021-P reverse cud population provides a modern case study in die failure frequency. Each of the six entries documents a unique fracture — differing in rim position, fragment size, and resulting cud shape — making the complete set valuable for studying the range of rim failure patterns on the Shield Cent reverse.
Attribution History
- Discovered by Matthew Vallee
- CU-1C-2021-06R
- Expert attribution by Cuds on Coins
External References
Community & Reference
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