Compositional study of slips and paintings in San José and Santa María pottery (Yocavil valley, Northwest Argentina): an approach by non-destructive and complementary techniques

From a multidisciplinary perspective, we propose a first comparative study on the pigments of archeological pottery San José and Santa María of Yocavil valley, Province of Catamarca, Northwest Argentina (ca. S XI–XVI AD). Both stylistic sets share a color palette in which the black, red and cream tones are structured. Considering that we are handling objects of cultural heritage, an analysis strategy was developed that combines non-destructive techniques (XRFp and XRD) and minimally destructive sampling methods with other techniques (EDS and micro-Raman spectroscopy) for the characterization of elements and crystalline phases in pigments. The results show not only some shared features—as hematite in red paints and cream slips resulting from a low-iron clay base preparation—but also some diversity in the composition of the pigments—as presence of rutile in some red paints and pyrolusite or series of solid solutions in the system manganese–iron oxides in black pigments. Graphic abstract