Variaciones del color. Primeros estudios físicoquímicos de las pinturas rupestres de La María, provincia de Santa Cruz

Abstract

In this paper, the initial results of the physico-chemical analyses of the rock art of the La Maria archaeological locality, Santa Cruz province, are presented. A micro-stratigraphic approach, a novel methodology for the study of pigments in Southern Patagonia, was implimented. Samples were analyzed using scanning electron microscopy with energy-dispersive X-ray spectroscopy and micro-Raman spectroscopy. This methodology enabled the main colors found in the locality (red, white, yellow and black) to be characterized in elemental and molecular terms. Results show that the composition of the paintings is heterogeneous, even within each tone. These data highlight the use of different iron oxides as pigments for red and yellow paintings. Manganese oxide and charcoal were used for black and calcium sulfate -- and probably kaolinite -- for white. In addition, gypsum was used as a filler in some cases. Finally, thescope, limits and future challenges of this research are discussed.