Insights from a tribological analysis of the tribulum

Since the 1980s, “strange” microwear traces were found to occur on flint blades from sites in the Near East from the late Neolithic and occurring in great abundance by the Early Bronze Age. Although these were considered by archaeologists to be sickles because they had visible gloss on their edges, their use-traces could not be reproduced in harvesting experiments carried out in the field. Subsequently, several lines of evidence were used to study the blades, including not only direct observation of microscopic wear traces, but also Near Eastern cuneiform texts from the third and second millennium BC describing agricultural instruments and analogy with ethnographic and experimental reference material. We found that these tools and their traces best matched traces on flint used to arm the underside of a tribulum (threshing sledge) for threshing grain and cutting straw. We built a replica of the tribulum described in cuneiform texts from the Bronze Age, using copies of the Bronze Age blades, and used this instrument in experiments.