Studying lithic microdebitage with a dynamic image particle analyzer

Lithic microdebitage has great archaeological potential to elucidate ancient stone tool production. So far, archaeologists have collected soil samples, separated them into size fractions, and analyzed them manually under a microscope to identify microdebitage. This time- and labor-intensive process has limited the number of samples and introduced intra- and inter-observer errors. Here, we discuss lithic microdebitage analysis with a dynamic image particle analyzer. This machine takes videos of soil particles as they fall from a chute. Software tracks them and measures their dimensions. Since sieving is no longer necessary, microdebitage analysis proceeds more quickly and processes samples within a few minutes. The standardized output allows the objective analysis of lithic microdebitage. We compare the angularity of c. 120,000 particles in an archaeological soil sample with experimental microdebitage. While the distributions show intriguing overlaps, we conclude that the most angular archaeological particles are not microdebitage but reflect a software glitch.