Non-destructive characterization of Della Robbia sculptures at the Bargello museum in Florence by the combined use of PIXE and XRF portable systems

"In situ"non-destructive characterization of the blue pigments presen in the ceramic glazes o fDella Robbia sculptures have been carried out at the Bargello museum in Florence. PIXE and XRF portable systems have been used to determine the matrix composition and the trace-elements,respectively.The results indicate that the arsenic is present as trace-element only after 1520.