SKH-1c-1986-06 Spiked Head

Description

Die cracking at the portrait high point was far from uncommon on 1986 Philadelphia Lincoln cents, and SKH-1c-1986-06 adds another data point to the fifteen-variety spiked head census for this date. The copper-plated zinc composition adopted in 1982 introduced a harder planchet surface than the former solid bronze alloy, increasing the mechanical load on each die impression. While individual strikes generate pressures exceeding 40 tons, it is the cumulative effect of millions of these loading cycles that fatigues the die steel at its most vulnerable geometry — the abrupt transition from the deeply recessed portrait cavity to the surrounding flat field. SKH-06 documents yet another working die that succumbed to this predictable failure mode, producing a crack that grew from Lincoln's crown outward into the obverse field. For collectors assembling a comprehensive 1986-P spiked head set, each variety carries distinct crack morphology: the angle of propagation, the crack's width, and how far it extends toward the rim all differ from die to die because crack paths follow the microscopic grain boundaries and inclusions unique to each piece of steel. These subtle geometric differences are what allow attributors to distinguish SKH-06 from the fourteen other documented varieties. Struck at Philadelphia on copper-plated zinc planchets (97.5% zinc, 2.5% copper) at 2.5 grams and 19mm.

Attribution History

• Discovered by Zach Llewellyn
• Cross reference: none. 06/13/2018.
• Expert attribution by Cuds on Coins

External References