Direct identification of organic colourants in heterogeneous matrices of cultural heritage objects with very little or no sampling remains a challenging analytical task.
A Raman procedure was investigated for the direct identification of archaeological organic-coloured pigments found in works of art, without solvent extraction. Conventional micro-Raman spectroscopy (MRS) using different excitations and surface-enhanced Raman scattering (SERS) were tested on microscopic samples of paints and cosmetics containing dyes from different sources (animal or vegetal). A tiny lump of purple pigment discovered during excavations in the ancient Minoan city of Akrotiri, on the Santorini Island in Greece (1650 B.C.) and Greco–Roman pink cosmetics were studied. In some cases the results were compared with a range of lake pigments made in the laboratory following historical recipes. Copyright © 2008 John Wiley & Sons, Ltd.