The elusive case of Pampeanbifaces.Traditional and fatty acids analyses

NORA FLEGENHEIMER; NATALIA MAZZIA; CELESTE WEITZEL; MARIANO COLOMBO

Simposio; 11th Symposium on Knappable Materials : From Toolstone to Stone Tools; 2017

Unifacial tools traditionally characterize lithicassemblages in the Pampean region, bifaces are considered exceptional, exceptin Late Pleistocene-Early Holocene occupations where they can be frequent. Yet,recent excavations in an orthoquartzite quarry with Middle and Late Holocenedates has produced an important number of bifaces. We here analyze two groups of bifaces: one from ElPicadero quarry, Tandil and the other from early occupations at Cerro ElSombrero and Cerro La Chinafrom special purpose and domestic sites.We apply both traditional lithic analysis tounderstand biface technology and life history, and fatty acids analyses tofocus on their uses/functions. As expected, bifacesizes differ, with larger andheavier bifaces in the quarries; but contrary to expectations, both samplesexhibit evidences of use on organic resources. Based on these analyses the roleof these bifaces and practices related to their disposal in relation to sitefunction are considered.Also,their absence in many pampean collections and its possible relation to rawmaterial distribution is discussed.