Part VI. Striking Errors:
Off-center Strikes:
Cupped Off-center Strikes
Definition: As is the case with broadstrikes, off-center strikes can show degrees of cupping ranging from nil to 90 degrees. In many cases there’s no obvious cause for the cupping. In other cases, the unstruck portion of the planchet is forced up by a stiff collar.
This 2000 cent shows extreme cupping with no obvious cause. The wall sticks up about 75 degrees from the horizontal. No trace of a collar scar is visible on the reverse face (the face struck by the anvil die).
The unstruck portion of this 1985 cent shows significant cupping. It was forced up as the planchet was driven past a stiff collar. This specimen is therefore a combination of an off-center strike and a stiff collar error. The collar scar is starkly obvious on the reverse face.