Laser cleaning of a bronze bell

In this paper we report the experimental results of the study of evaluation of an UV laser cleaning treatment on a bronze bell outdoor, dating from the second half of the 600. Energy dispersive X-ray fluorescence (EDXRF) non-destructive analysis was performed on the bell before, during and after the cleaning treatment in order to assess the laser ablation threshold, to define the efficiency of laser cleaning process, to avoid possible damage of laser on the bell, to determine the concentration of the constituents of both the patina and the alloy. In particular, an EDXRF portable apparatus was used in order to evaluate the variation of concentration of sulfur, chlorine, calcium, copper, lead and tin during the laser cleaning.