Direct analysis of the central panel of the so-called Wyts triptych after Jan van Eyck

The applicability of mobile, non-destructive techniques such as energy dispersive X-ray fluorescence spectroscopy, which reveals the elemental composition, and fibre-coupled Raman spectroscopy, offering molecular information, is applied to the central panel of the Wyts triptych, after Jan van Eyck. Using a combination of these direct techniques, vermilion (HgS), lead white (2PbCO3·Pb(OH)2), anatase (TiO2), massicot (PbO), zinc white (ZnO) and lead-tin yellow type I (Pb2SnO4) could be identified. X-ray fluorescence spectroscopy (XRF) measurements also confirmed the presence of cobalt. Also, copper was detected in different blue and green areas. For the brown and red colour, iron oxides were used. Apart from identifying pigments, the combination of these analytical techniques also gave information about restored parts and the layered structure of the panel. XRF maps of three different areas of the panel painting were recorded to get an idea of the changes the painting underwent during its past history. This research confirms the results of the visual analysis that the painting is a heavily restored copy of a lost original by Jan van Eyck.