New insights into the Spanish Levantine rock art pigments combining pXRF and stylistic approach: The Coco de la Gralla site (Mas de Barberans, Tarragona, Spain) as a case study

Abstract

Designated as a World Heritage Site in 1998, Spanish Levantine rock art represents a unique form of open-air pictorial expression in prehistoric Europe. Over the past decades, numerous studies have sought to define its stylistic sequence, thematic content, and territorial distribution to refine its still-uncertain chronological framework, given the impossibility of obtaining reliable radiocarbon dates from pigments. Despite these advances, the composition of the pictorial layers remains largely unexplored, and stylistic analyses incorporating a technological perspective are still lacking.

This paper presents a non-destructive analytical protocol for the in situ elemental characterization of Levantine pigments using portable X-ray fluorescence (pXRF). A detailed examination of rock wall alterations, combined with a stylistic analysis of the paintings and statistical data processing, enabled an assessment of pXRF’s potential for characterizing and distinguishing prehistoric pigments.

The implementation of this protocol at Coco de la Gralla site (Tarragona, Spain) has yielded interesting results pointing to a significant correlation between some mineral elements concentration composing the red pigments and the stylistic variants identified in human depictions. These findings are discussed in light of the pigments’ elemental composition and the different stages of their preparation, while also addressing rock wall alteration and the inherent limitations of pXRF detection.

Our research presents a non-destructive method for conducting preliminary screenings to explore technical traditions at different temporal and territorial scales. This approach opens new pathways for redefining Levantine stylistic horizons by integrating formal and technological variables.