Untersuchungen an römischen Wandmalereien

Abstract

Fragments of Roman wall painting from Switzerland have been investigated by electron microscopy, X-ray and electron diffraction, electron microprobe analysis and by X-ray fluorescence spectroscopy. X-ray fluorescence showed that the significant elements of the pigments were copper, calcium and silicium for blue, and iron for yellow, red, brown and light green specimens, respectively. By X-ray diffraction and selected area electron diffraction Egyptian Blue CaCuSi₄O₁₀ could be evaluated. Red pigments give X-ray patterns of Hematite α-Fe₂O₃. From microprobe analyses, the author considers yellow pigments to be Ochres (Kaolinite with traces of a-FeOOH) and light green pigments Glauconite, a clay mineral containing Fe²⁺ and K⁺. The structure of the painting was evaluated and compared with Vitruv’s instructions. The technical quality of the specimens described seems to be much lower than that of specimens from Italy, which have been described in the literature.