The first identification of composite paints with proteinaceous binder in Upper Palaeolithic (31–23 ka) organic decorations
Research of coloring pigments and binding compounds from the Upper Palaeolithic (UP), including on portable art objects such as personal ornaments, provides new insights into social and cultural aspects of human history. However, we lack a comprehensive study of the composite pigment mixtures and binding materials that were produced intentionally and used for coloration. The study of several personal ornaments from the UP layers dated 31–23 ka calBP in Mezmaiskaya Cave, North Caucasus (Russia), shows that UP paints have a complex chemical composition. Using ATR–FTIR and SEM–EDS, we have identified that for coloring organic personal decorations UP humans used composite paint mixtures produced from organic (bitumen) and inorganic (red bolus/kaolin) natural pigments. Also, we firstly identified that UP humans applied a proteinaceous binder, likely representing a kind of the gelatine type animal glue, which they intentionally produced from animal origin materials using boiling. This is the oldest evidence of boiling placing its origin at about 30 ka within the late UP and linking this innovation to the need of producing organic binding material for dyeing rather than with the food preparation.
