Use of Non-Invasive Xrf Spectroscopy for the Analysis of Mudejar Polychrome on the Chapel Door in the Palace of the Dukes of Alba in Seville

Abstract

The pigments, execution technique and repainting used on the polychrome wood door of the chapel of the Palace of the Dukes of Alba in Seville (Spain), best known as Palacio de las Duenas, were studied using portable X-ray fluorescence equipment. This carpentry work is a magnificent example of the Mudejar art made in Spain in the early 16th century. Portable X-ray fluorescence gave good information on the different components of the polychrome. The following pigments were characterized: red (cinnabar/vermilion, lead oxide, iron oxides, and a mixture of iron oxide and orpiment/realgar), black, white (white lead) and yellow (orpiment/realgar and yellow ochre). Brass was also found in metallic sheets which decorate the door and iron in the bolt which locks it. The pigments were applied with the oil painting technique over a support layer that had been primed with animal glue. This support layer was gypsum in some cases and white lead in others. This study is essential to the polychrome conservation of the studied artwork, and it will help clarify uncertainties in the history and painting of Mudejar art.