BLADE TOOLS
A stone blade is really just a long parallel-sided flake, as the drawing shows. It has sharp cutting edges, and makes a very useful knife. The real trick is to be able to make one. It is almost impossible to make a blade out of any stone but flint or a natural volcanic glass called obsidian. And even if you have flint or obsidian, you first have to work up a special cone-shaped “blade-core,” from which to whack off blades.
PLAIN BLADE
You whack with a hammer stone against a bone or antler punch which is directed at the proper place on the blade-core. The blade-core has to be well supported or gripped while this is going on. To get a good flint blade tool takes a great deal of know-how.
Remember that a tradition in stone tools means no more than that some particular way of making the tools got started and lasted a long time. Men who made some tools in one tradition or set of habits would also make other tools for different purposes by means of another tradition or set of habits. It was even possible for the two sets of habits to become combined.