Investigation of a naturally patinated bronze artifact originating from the outdoor statuary group of Mathias Rex

Abstract The present work aims to investigate the morphology and composition of natural patina formed after long-term atmospheric exposure (∼100 years) on the bronze screws used in assembling the statuary group of Mathias Rex, placed in the center of Cluj-Napoca, Romania. The chemical composition of the bronze and of the natural patina, formed on the screws’ surface were determined by X-ray fluorescence analysis, and the morphology of the latter was determined by SEM - EDX cartographies.