Characterizing the chemical composition of red coloring matter samples from the Altamira cave using synchrotron µXRF imaging

José Tapia (1, 2) , Myriam Eveno (2, 3) , Alfredo Prada , Pilar Fatás , Carmen de las Heras , Pablo Arias , Katharina Müller (4) , Sebastian Schöder (5) , Ina Reiche (1)

1 Lab-BC UAR3506 - Laboratoire de développement instrumental et de méthodologies innovantes pour les Biens Culturels
2 IRCP - Institut de Recherche de Chimie Paris
3 C2RMF - Centre de recherche et de restauration des musées de France
4 IPANEMA - Institut photonique d'analyse non-destructive européen des matériaux anciens
5 SSOLEIL - Synchrotron SOLEIL

The chemical in situ study of red coloring matter from Paleolithic cave art is challenging because the same trace elements can be present both in the matter and in the calcitic support, and the two present a heterogeneous composition. In this study, thirteen red iron oxide-based coloring matter samples obtained at drip points coming from eight locations within the Techo de los Polícromos, Altamira cave (Spain), have been analyzed by highly sensitive synchrotron-induced micro-X-ray fluorescence (SR-μXRF). Our analyses improved the characterization of red Paleolithic pigments by establishing characteristic trace element patterns, additionally facilitating a comparison of the distinct representations within the cave. Furthermore, new differentiation criteria between the composition of the calcitic walls and that of the red coloring matter could be established, helping to improve future non-invasive analyses.

Mots clés: SR-µXRF; Elemental imaging; Paleolithic cave art; Red coloring matter; Iron oxides; Altamira cave

Domaines: Art et histoire de l'art

José Tapia, Myriam Eveno, Alfredo Prada, Pilar Fatás, Carmen de las Heras, et al.. Characterizing the chemical composition of red coloring matter samples from the Altamira cave using synchrotron µXRF imaging. Applied physics. A, Materials science & processing, 2024, 130 (11), pp.813. ⟨10.1007/s00339-024-07950-5⟩. ⟨hal-04767384⟩