I was leaning towards a lamination crack. It seems to fit this definition, I think? I did not suggest die crack.
Source: http://www.error-ref.com/?s=lamination+crack
Quote:
A lamination crack is one common manifestation of a lamination error. The surface of the coin simply cracks and may lift up slightly on one side.
A lamination crack is one common manifestation of a lamination error. The surface of the coin simply cracks and may lift up slightly on one side.
Source: http://www.error-ref.com/?s=lamination+crack























