In situ characterization of prehistoric rock paintings: the Côa Valley (Portugal)

A study of prehistoric rock paintings in the Côa Valley, Portugal, reveals that hematite is the predominant pigment used in these ancient artworks. The research utilized in situ color spectrophotometry and portable Raman spectroscopy to analyze red motifs across four sites within the archaeological complex. Findings indicate that while hematite dominates the pigments, goethite, quartz, and feldspars are also present, suggesting potential use of ochre or natural elements from the backdrop stones. This non-invasive methodology provides valuable insights into the composition and preservation of prehistoric rock art, contributing to a deeper understanding of human creativity and material culture during ancient times.

Pozo Antonio, J. S., Rivas, T., Barreiro, P., Caetano, V., Carrera, F., & Alves, L. B. (2023). In situ characterization of prehistoric rock paintings: the Côa Valley (Portugal). Proceedings of the 2022 IMEKO TC4 International Conference on Metrology for Archaeology and Cultural Heritage, 502–507. https://doi.org/10.21014/tc4-arc-2023.095