Cud Errors Explained

A cud on a coin is a damaged area resembling a blob at the edge of the coin. Cuds result from a piece of the perimeter of the die breaking away (image). They can be any shape depending on the shape of the piece that broke off the die. On the opposite side of the cud there will be weakness in the strike (image) unless it's very small.

A retained cud happens when there is a die crack from rim to rim (image below) but the piece is still attached to the die. If the die is not retired in time, this can eventually fall off completely and make full fledged cuds.

New collectors can sometimes mistake damage to the coin for cuds. Commonly rim dents. (image)

Click images to enlarge.