Die deterioration doubling - Errors and varieties
This error is due to a deterioration of a die (die wear and die fatigue). It sometimes results as a doubling. It is noticeable in several ways. The surface of such doubling is rough, more or less defined, of different widths and whose contours are rounded. It starts with one or a few places on the die, to gradually expand on it.
Die Deterioration Doubling (DDD) may completely surround part of the design like numbers and letters.
Die deterioration can cause other marks on a coin like trails.
Die Deterioration values
Only in very rare instances, like when it affects the date, die deterioration might worth a bit more than a regular coin.