Visualization of As(<scp>iii</scp>) and As(<scp>v</scp>) distributions in degraded paint micro-samples from Baroque- and Rococo-era paintings

Abstract

Orpiment and realgar are two artists' pigments that appear not to be stable upon light exposure, quickly degrading to arsenic trioxide and arsenate. Their identification appears challenging but can be overcome by the use of synchrotron based techniques such as μ-XANES.