Characterization of Brazilian artists' palette from the XIX century using EDXRF portable system

The palette of some of the most representative Brazilian painters from the XIX century was characterized using EDXRF technique. In this work were analyzed paintings of: Eliseu Visconti, Almeida Junior, Rodolfo Amoedo, Henrique Bernardelli, Rafael Frederico, Modesto Brocos, Augusto Rodrigues Duarte and Pedro Peres - all of them belonging to the National Museum of Fine Arts Collection. EDXRF measurements were carried out with a portable system developed by the Nuclear Instrumentation Laboratory, consisting of an X-ray tube Oxford TF3005 with tungsten (W) anode, operating at 25 kV and 100 μA, and a Si-PIN XR-100CR detector from Amptek. In each color and distinct hue of the paint layer were obtained several spectra, with an acquisition time of 300 s and a beam collimation of 2 mm. The spectra were processed and analyzed using the software QXAS-AXIL from IAEA. Some pigments used by the artists were: zinc white, lead white, ochre, umbra, vermilion, Prussian blue, cobalt blue, cadmium yellow, black iron oxide, manganese violet, etc. These results - together with the Computed Radiography analyses - have been used to create a database about the XIX century collection of the National Museum of Fine Arts, in order to assist restorators, conservators, art students and researchers in the field of archaeometry