SKH-1C-2023-03 Spike Head

Description

Rounding out the initial trio of 2023 Philadelphia Lincoln Shield cent spike heads, SKH-1C-2023-03 completes the initial trio of documented die crack varieties for this production year. The three 2023 spike heads cataloged thus far represent early documentation in what will likely continue to expand as additional specimens are submitted and evaluated — the 2021 census reached into the mid-40s, demonstrating the potential scope of spike head discovery within a single production year. Each of the three 2023 entries (SKH-1C-2023-01, -02, and -03) originates from a distinct obverse die, identifiable by the unique geometry of its crack path and the resulting spike profile on struck coins. The underlying mechanism is consistent across all spike heads: cyclic fatigue loading during high-speed production striking initiates micro-cracks at stress concentration points within the fine hair detail at the top of Lincoln's portrait, and these cracks grow incrementally until they breach the die surface, creating a channel that fills with planchet metal and produces the raised spike. Modern cent production at Philadelphia employs high-speed presses that can produce over 750 coins per minute per press, subjecting each die pair to hundreds of thousands of strike cycles over its service life. The copper-plated zinc planchet composition used since 1982 interacts differently with die surfaces than the preceding solid bronze alloy, and the zinc core's tendency to adhere to die surfaces may contribute to accelerated die deterioration in the high-relief portrait areas. The Cuds on Coins catalog system provides collectors with unique identifiers for each documented spike head, enabling systematic collection and attribution. Visual inspection at 5-10x magnification of the top of Lincoln's head is the standard examination technique for identifying spike head varieties.

Attribution History

• Discovered by Matthew Vallee
• SKH-1C-2023-03
• Expert attribution by Cuds on Coins

External References