Examples from the Web for hammerstone
Historical Examples of hammerstone
This seems more likely to be a hammerstone used for chipping.
Hammerstone (L)—a hard pebble showing battering from use as a hammer.
Direct Percussion—flaking flint by striking it directly with a hammerstone or other object.
The hammerstone shown in Fig. 41 was found on the surface near the head of Priest Rapids.
The rim of the bowl is flattened, and this flat surface resembles that of the part of a hammerstone used for pecking.