How do you like your cereal? A qualitative and quantitative use-wear analysis on archaeological grinding tools from prehistoric Greek sites

Abstract

Abstract Cereals and pulses have formed staple foods for the populations of the European continent ever since the emergence of agriculture, yet the ways in which they have been processed were by no means homogeneous in time and space. This study deals with use-wear analysis of prehistoric grinding stones from a series of Neolithic (7th-4th millennium BC) and Bronze Age (late 4th-2nd millennium BC) sites in mainland Greece focusing in particular on cereal-processing and the action of cereal dehusking. Optical observations through a stereomicroscope and a metallographic microscope have been combined with surface measurements (laser scanning confocal microscopy) and characterization (method of continuous wavelet transform and SMa coefficient that indicates the arithmetic mean value of the multi-scale decomposition of a surface). Comparison between experimental surfaces (from replicated tools used to grind various plant-foods) and archaeological ones permitted to distinguish archaeological tools used for cereal processing from those employed for processing other plant-foods. Furthermore, it was possible to determine the formation of different use-wear signatures depending on whether the cereals were processed in their husked or dehusked form. The tools used to process husked cereals produced higher SMa values compared to those related to dehusked cereals. Husks seem to function as an abrasive agent which creates less extended plateaus of more rough texture on the tools surfaces. These results show that grinding tools may have been (occasionally) implemented in the dehusking process or that dehusking was not always conducted prior to grinding, at least in the Neolithic period, or both. Nevertheless, variations have been detected even within the same chronological period attesting to the diversity of food processing and cereal meals.