PART II. Die Varieties:

Broken Punch

Definition: A broken punch that is used on a master or working die to create a design element or mintmark.

The mint mark punch used to make the D mint mark on all the working dies of 1979 Lincoln cent had a split on the lower serif.

This is broken punch when transferred onto the working die is commonly mistaken for a Repunched Mintmark, which it is not.