From Giotto to De Chirico to Verrocchio: analyses of paintings and historical bronze alloys availing of portable EDXRF equipment

Energy-dispersive X-ray fluorescence (EDXRF) has been used successfully for some time now in non-destructive diagnostic examinations of art works, especially for paintings and bronze works. Furthermore, such examinations may be carried out with portable equipment, allowing studies in situ. EDXRF-analysis of paintings generally provides the following information: –possible presence of elements on the surface (sulphur, chlorine) due to pollution; –identification of the elements, and therefore giving a good indication of the pigments, employed by the artist; and –identification of previous restoration areas, by detecting the presence of “modern” elements, such as titanium, zinc, cadmium, etc. Recently, the famous Chapel of the Scrovegni painted by Giotto in Padua in 1303–1305 was analysed in detail to obtain all the information described above. Another example of application of EDXRF-analysis to paintings was a recent examination of 11 paintings believed to be by De Chirico the outcome of which was compared with that obtained for 15 paintings certainly by De Chirico. Finally, the bronze statue of Bartolomeo Colleoni was analysed, in order to determine its composition and the presence of sulphur and chlorine on the surface. In this case, the analysis was partially destructive, because small areas of a few square millimetres had to be cleaned for analyses, to avoid interference by the patina.