The conservation-restoration of the Capitoline She-Wolf: stratigraphic characterisation of the alteration and deposition materials present on the famous bronze statue, symbol of Rome

The re-structuring of the exhibition halls of the Capitoline Museums offered the opportunity to develop a conservation-restoration project on the bronze statue of the Capitoline She-Wolf, which dates from the V century BC. The project took into consideration not only the preservation aspects but also the potential to gather further historical knowledge about this famous bronze artefact. This paper deals mainly with surface alteration and deposition products and presents research that compares information collected through a documentation survey with the results of scientific examinations carried out on samples collected from the statue’s surface. The survey showed that the She-Wolf was exposed for a long time in an outdoor environment before being exhibited in the Museum. Optical microscopy of cross sections, SEM-EDX, FTIR, as well as Py-GC-MS, has been used to characterise the composition of both the inorganic and organic surface components. The chemical composition of the bronze patina reflects stratigrafically the exposition history of the statue and its characterisation has been of the utmost importance in the interdisciplinary decision-making process relating to the conservation methodologies and procedures to be adopted. In particular, in order to recover the archaeological surface, a thick layer of natural organic substances (drying oils, waxes) applied during previous maintenance treatments which gave the bronze surface a dark brown appearance, have been removed.