Integrated study of Neolithic rock art at the Rocher du Château, a striking rock on a transalpine route (Bessans, Savoy, Vallée de la Maurienne, France)
Résumé
Being one of the ten alpine sites of schematic rock art painting, the Rocher du Chˆateau(Castle Rock) is a remarkable site situate on a main transalpine route at 1750m.a.s.l. inthe Vall ́ee de la Maurienne (France). Despite the first mention of the presence of rock art,few studies have been carried out on this site (Nehl, 1976). Since archaeological surveys andsome archaeological excavations were realized (between 1989 and 2003) attesting a Neolithicoccupation and the discovery of some coloring and colored matter from the Neolithic layersattributed to the phase 2 of the ”Square Mouthed Pottery” Italian culture (4500-4000 BCE).In order to question the chronology of the ”schematic” painting phenomena occurring in theMediterranean area, the integrated study of the Rocher du Chˆateau involved both the rockart description and the comparaison between fragments of coloring materials to the paint-ing matters preserved in the bedrock surface. By combining non-invasive in situ methods(numerical binocular and Raman spectroscopy) and micro-sampling, the understanding ofweathering process before and after painting deposit is proposed and the identification of thepigment is realized. Complementary physico-chemical analyses have been developed at sev-eral scales of observation to identify various compositions of the fragments of coloring matter and of the colored pebble fragments. Thanks to these data, discussion could be proposed tounderstand the potential link between the artefacts, the production of coloring matter. andthe application of painting matter. The presence of an extremely unusual mineral of ironsilico-phosphate raises the question of the origin and of the supply in coloring matter