Early Use of Pressure Flaking on Lithic Artifacts at Blombos Cave, South Africa

Pressure flaking is a method of forming points, grooves, and notches on stone tools in which a tool is pressed up against another stone, instead of striking it. It has been thought to be a fairly recent innovation, arising in the Upper Paleolithic 20,000 or so years ago. Mourre et al. (p. [659][1]), show that tools from Blombos Cave, dating to about 75,000 years ago, have grooves and patterns resembling production by heat treatment followed by pressure flaking. Replication experiments were performed using similar source material followed by microscopic study of the tools. Despite the evidence for an early innovation, it seems that pressure flaking was not used widely elsewhere until much later; thus, such early innovations may have been sporadic ephemeral. [1]: /lookup/doi/10.1126/science.1195550