PART V. Planchet Errors:
Upset Mill Errors:
Coin Struck on a Type I Blank:
Definition: This error type occurs when a blank does not pass through the upset mill and it is struck as a coin. Because it is not rolled and squeezed to a smaller diameter, no proto-rim is generated along the outer margin of the blank. The edge is also not smoothed out, and instead retains a rough, cut-and-tear texture.
This copper-plated zinc cent was struck off-center on blank. The outer margin of the blank is flat. It lacks the elevated proto-rim of a planchet (“Type II planchet”). Even though the edge of the blank was plated with copper before the strike, it still shows the rough, cut-and-tear texture that is usually seen on blanks and that results from the blank being pushed through a hole in a perforated base plate by the blanking die (punch). It is very rare to find a copper-plated zinc cent that is struck on a blank. We are aware of only three examples.