Fig. 5

Detail of light microscopic image of the Heem sample under white light (a), ultraviolet (b), backscatter electron image (c) and detail d showing layers 3–4, the detail is indicated with a red box in c. Elemental maps of carbon (e), calcium (f), iron (g), silicon (h), lead (i), arsenic (j), aluminum (k), and tin (l) are obtained with the SEM/EDX. False color-plots ATR-FTIR images at 1722 cm⁻¹ (m), 791 cm⁻¹ (n), 1028 cm⁻¹ (o), and 1400 cm⁻¹ (p) (red is representative for high intensities). Part of ATR-FTIR spectrum of a sum of many spectra from the ground (layer 1, black line), iron-containing layer (layer 3, blue line), orpiment layer (layer 5, red line) and lead white layer (layer 6, green line) (q). Arsenic -K-edge XANES spot analyses taken from an intact arsenic sulfide particle in the lower part of the paint layer (layer 5, red line), upper part of the degraded paint layer (layer 5, blue line), calcium-containing ground layer (layer 1, green line) and the lead white-containing top layer (layer 6, black line) (r)