Results of petrographic analysis of stone assemblage from the Kosa Mesolithic sites (Northern Kama region)

Abstract

In this paper, the results of petrographic analysis of stone materials from the Mesolithic sites of Kosa 1–3 in the northern Kama River area (Perm Region) are discussed. The sites of Kosa 1 and 2 are located on the second terraces of the Lolog and Kosa Rivers, and Kosa 3 — on the first terrace of the Kosa River. Kosa 1 and 2 are considered chronologically similar and belong to the Late Mesolithic period. The site of Kosa 3 is younger, and it marks the transition from the Mesolithic to the Neolithic. For the analysis, aimed at determining the ancient raw material strategies, selected were five stone artifacts from Kosa 1, five stone artifacts from Kosa 2, and eight samples from Kosa 3. Polarised microscopy was used for the petrographic study of stones in thin sections. This method allows the precise diagnosis of minerals and rocks based on their optical characteristics. The results indi-cate that flint and jasper were applied as main raw materials at all analysed sites. The choice of material for the stone industry at the sites was limited. Sandstone and siltstone were used for production of stone macro tools. The difference in raw source materials was determined for the Kosa 1 and Kosa 2 sites on one hand, and Kosa 3 on another — the main raw sources at the Mesolithic sites were flint and jasper, while at the Kosa 3 transitional site coloured pebbly flint was used. The comparison of the results with petrographic data from other Mesolithic sites of this region demonstrates similarity in the main principles of the strategy of raw source choices such as using flint and jasper. Furthermore, a larger variety of source raw materials has been determined for the sites of the Middle Kama River basin. The comparison with the results from the Late Stone Age sites also revealed a greater variety in the materials used in comparison with the Kosinsk sites (platy flints, cherts, tuffs, gabbro, and others). All raw materials were of local origin such as alluvial deposits of the Lolog and Kosa Rivers. The results of the petrographic analysis suggest the situational choice of materials for the manufacture of tools by the local population, with the main factor being their easy accessibility.