On the use of glaze and ceramic body analytical spectra in heritage azulejos as beacons of provenance

Abstract

During the past three years a research group including the Museu Nacional do Azulejo (Portuguese National Azulejo Museum), the Laboratório Nacional de Engenharia Civil and the HERCULES Laboratory of the University of Evora, acquired X-ray fluorescence spectra of the glazes of azulejo panels on site and single tiles from the collections of the Museum. That data was recently complemented by spectra obtained with the micro-analysis unit of a scanning electron microscope and with the AGLAE proton accelerator installed at the Carrousel du Louvre in Paris. By comparing spectra obtained on significative areas it is possible to obtain a glimpse of alikeness or of dissimilarity pointing to a similar or to a different officinal origin. This communication presents the method through a number of exemplificative cases.