SKH-1c-1990-03 Spiked Head

Description

Reported on April 28, 2024 — just under four months after SKH-02 — SKH-1c-1990-03 on the 1990 Philadelphia Lincoln Memorial cent continues the 2024 wave of spiked head documentation for this date. The rapid succession of discoveries suggests either a coordinated search effort among collectors focused on the 1990-P date or simply the statistical coincidence of multiple independent finds being submitted within a short window. Spiked head formation on copper-plated zinc Lincoln cents presents a nuanced die crack dynamic: the zinc core of the planchet is significantly softer than the copper plating layer, and this hardness differential means that metal flowing into a die crack during striking encounters varying resistance depending on whether the copper plating or zinc substrate reaches the crack first. On very fine cracks, the copper plating may bridge the gap without significant metal intrusion, producing only a faint line; wider cracks allow the zinc substrate to flow into the opening beneath the copper plating, creating a spike with a copper-coated surface over a zinc core. This compositional structure within the spike itself is unique to post-1982 zinc cents and differs from the homogeneous copper spikes found on pre-1982 specimens. Struck on copper-plated zinc planchets composed of 97.5% zinc and 2.5% copper, weighing 2.5 grams and measuring 19mm.

Attribution History

• Discovered by David Bennett
• Cross reference: none. 04/28/2024.
• Expert attribution by Cuds on Coins

External References