Hammerstones used for striking nodules to remove flakes, or used for retouching blanks into tools. These can be identified by crushing and abrasion on the ends.
Other knapping tools such as antler or bone percuussers are assumed from experimental replication, but are usually not preserved.

Hammerstones used for striking nodules to remove flakes, or used for retouching blanks into tools. These can be identified by crushing and abrasion on the ends.

Anvils are the stones on which cores are placed for bipolar technique and can retain crushing and abrasion in the middle rather than on the ends, from this process.