Definition: Severe impact damage that covers an extensive area on one or both die faces.  Such damage can result from the dies striking a large mass of foreign matter that is hard and brittle.  It can also result from a piece of a broken die or broken collar entering the striking chamber and shattering on impact.

Both of the dies that struck this 1998-D quarter were heavily damaged after installation.  In addition to widespread impact damage, the obverse die features a large cud (marginal die break).  The right side of the collar has also broken off, leaving a collar cud (collar break) that extends from 2:00 to 5:00 (obverse clock position).

It’s possible that the impact damage, cud, and collar cud were all generated when a large piece of brittle metal intruded into the striking chamber and shattered upon impact.  Alternatively, it could be that the process was initiated when a fragment from the obverse die or a fragment of the collar fell between the dies and exploded upon impact.