PART V. Planchet Errors:
Alloy Errors:
Ragged Perforations (a.k.a. “Blow Holes”)
Definition: A planchet defect in the form of a ragged hole. Such perforations typically develop as the coin metal strip is rolled out. Tensile stresses tear apart areas of the strip that are abnormally stiff and brittle. Openings appear that are usually characterized by an edge that is beveled on both faces.
Not all planchet holes are caused by tensile stresses. Some represent areas formerly filled by foreign matter or areas
from which an island of coin metal has fallen out. These holes do not have beveled edges.
Ragged perforations are closely related to ragged fissures, ragged notches, and some ragged clips. They all stem from the same cause
This 1979-P Jefferson nickel has been struck on a planchet with a ragged perforation (“blow hole”).
Images are courtesy of Heritage Auctions.
