Successfully Dating Rock Art in Southern Africa Using Improved Sampling Methods and New Characterization and Pretreatment Protocols

Abstract

Worldwide, dating rock art is difficult to achieve because of the frequent lack of datable material and the difficulty of removing contamination from samples. Our research aimed to select the paints that would be the most likely to be successfully radiocarbon dated and to estimate the quantity of paint needed depending on the nature of the paint and the weathering and alteration products associated with it. To achieve this aim, a two-step sampling strategy, coupled with a multi-instrument characterization (including SEM-EDS, Raman spectroscopy, and FTIR spectroscopy analysis) and a modified acid-base-acid (ABA) pretreatment, was created. In total, 41 samples were dated from 14 sites in three separate regions of southern Africa. These novel protocols ensure that the 14C chronology produced was robust and could also be subsequently applied to different regions with possible variations in paint preparation, geology, weathering conditions, and contaminants.

Combined 14C Analysis of Canvas and Organic Binder for Dating a Painting

“…In the case where inorganic pigmented paints is found, the vehicle used to bind the pigments is dated (Li et al 2012; Baker and Armitage 2013). However, due to relatively large amounts of sample material required (>20 mg material; Bonneau et al 2016), such methods have not been applied routinely for the analysis of modern and contemporary art.…”

Geomicrobial Investigations of Colored Outer Coatings from an Ethiopian Rock Art Gallery

“…There is an abundance of literature that highlights the cultural significance of rock art as well as the attempts to date paintings and petroglyphs in many parts of the world [31,32]. However, rock art is one of the most fragile forms of ancient heritage and its preservation is understudied.…”

Making visible the invisible. A microarchaeology approach and an Archaeology of Color perspective for rock art paintings from the southern cone of South America

“…These studies omit in general the description and morphological characterization of the layer contents, as well as the quantification, measurement, and distribution of its components or grains present in each one (Marte et al 2011 and; to illustrate our purpose see Chalmin et al, 2003;Vignaud et al, 2006;Gheco et al 2020, as they describe precisely what we want to sustain here). As a consequence, chemical characterization of the different layers, the eventual quantification of their composition, and the mixtures identified are interpreted as the result of different mixtures, or different paint pots, in other words, the elemental and molecular differences correspond to different recipes (Chalmin et al, 2003;Vignaud et al, 2006;Bonneau et al, 2016).…”