Identification of bifacial components in middle Paleolithic techno-complexes (based on the Chagyrskaya cave assemblages)

Previously, occasional bifacial tools found in different industrial variants of the Altai Middle Paleolithic were not considered as cultural markers that could be used to differentiate the technological/cultural variants. They rather were a bright but situational manifestation of the typological variability, especially in the case of the Sibiryachikha assemblages. Purpose. The article discusses various research approaches used to determine and evaluate the bifacial component in the Middle Paleolithic lithic assemblages, namely attributive analysis with a set of specific attributes, scar-pattern analysis and experimental modelling. Results. As a result of recent studies at the site Chagyrskaya Cave, the key-site of Sibiryachikha, we found out that all the bifaces were made using plano-convex technology. In the Chagyrskaya Cave assemblage all stages of bifacial production have been noticed? including pre-forms, bifacial tools and tools made on bifacial thinning flakes, accompanied by numerous bifacial thinning flakes and bifacial thinning chips. Re-investigation of the Okladnikov assemblage should bring a new, previously unknown series of technical spalls related to the bifacial plano-convex technology. A similar situation is with Karabom complexes, where all bifacial tools are made using bi-convex bifacial technology. Thus, criteria for technological distinction of bifacial production are of special importance. Conclusion. Our experiments have shown that the proportion of chips associated with bifacial production is much higher than it can be determined while analyzing archaeological assemblages. Taking in account the new data on bifacial technologies in the region, we conclude that variability of Middle Paleolithic complexes has become more complex. To evaluate the bifacial component in Paleolithic assemblages, all stages of bifacial flaking should be documented, including bifacial pre-forms, technical spalls related to bifacial reduction sequence, chips, blanks which demonstrate bifacial flaking errors and tools made on bifacial thinning flakes and bifacial tools. A complete set of bifacial production is present at the Chagyrskaya Cave assemblage due to the fact that the cave was constantly visited and had a sufficiently long habitation cycle as a source of raw materials. In the assemblage, a complete sequence of lithic raw material exploitation was processed. Taking into account the fact that Chagyrskaya Cave and Okladnikov Cave are associated only with Neanderthal remains, it can be assumed that bifacial plano-convex technology in the Middle Paleolithic of Altai is linked to Neanderthal population in the region.