1972 Lincoln Memorial Cent - SKH-1c-1972-09 Spiked Head

Description

Attributed on March 6, 2018, by the Cuds on Coins team — less than three weeks after SKH-1c-1972-08 — the ninth spiked head for the 1972 Philadelphia Lincoln Memorial cent extends the early-2018 wave of new discoveries for this date. No cross-references have been documented. The close temporal proximity to the eighth attribution suggests renewed collector interest in searching 1972 Philadelphia cents during the first quarter of 2018, possibly stimulated by the publication of SKH-1c-1972-08 itself or by broader community awareness of the collecting opportunity these varieties represent. The ninth variety carries its own unique spike geometry determined by the microstructural characteristics of its specific die: the path a fatigue crack follows through die steel depends on local grain boundaries, carbide distributions, prior heat treatment effects, and the stress intensity at the crack tip as it propagates from the interior cavity wall toward the die face. These metallurgical variables ensure that no two dies produce identical spikes, giving each catalog entry its own diagnostic fingerprint. SKH-1c-1972-09 preserves one such fingerprint — the physical record of how crack number nine made its way through the steel of its particular die and emerged as a raised feature on the coins it produced.

Cross References

• Cross reference: none. 03/06/2018.

External References