Derestauro e restauro della pisside skyphoide sovradimensionata a figure rosse da Locri Epizefiri: una metodologia di intervento a più criticità conservative

The thesis paper concerned the design of solutions to serious conservative problems of a skyphoid pyx coming from the National Archaeological Museum of Palazzo Nieddu del Rio and other fragments without a placement attributable to her style and era. Whereas these archaeological finds are mentioned in a few bibliographical sources and have not been the subject of further study on the previous restoration and their exploitation, in order to propose a plausible reconstruction of the context of origin, a bibliographic research activity of all the information necessary to frame the vase through stylistic and inconographic comparisons was started, with the aim of framing the chronology and the historical context of belonging. Except for the fragments without a placement, the lid and body of the vase arrived at the restoration laboratories of the JRC La Venaria Reale on an exhibition stand and showed large gaps, two types of integration gypsum distributed not homogeneously, obvious traces of previous restoration (polyvinylacetate), widespread silicatic encrustations, deep mechanical damage, and a strong decohesion of the black paint on almost the entire surface. The FTIR spectrophotometry allowed the identification of the chemical nature of the encrustations and of the materials attributable to previous interventions (gypsum and polyvinyl-acetate), and then to identify the correct methodology for their removal. For the study of the state of preservation, was used autopsy examination of the photographic documentation obtained in UV light and stereomicroscope, also with the aim of monitoring the cleaning phase. After having addressed the problems related to the decohesion of materials and the removal of silica encrustations with the aim of improving the readability of the object, was found an alternative method to traditional integration (which would have involved almost half of the product with results potentially susceptible to criticism) to solve the problem of the large gap, giving unity to the set of fragments and, at the request of the Authorities, allowing to change the position of the fragments so as to leave open the possibility of integrating the vessel in view of a possible future discovery of further relevant fragments. Specifically, the vase was set up on an exhibition stand to which all fragments adhere only through the attractive force of neodymium magnets. On this theme a verification activity of the properties of the magnets has been set up, to evaluate their effective adaptability to the specific case of the pyx, investigating the interactions of the materials chosen for the intervention if subjected to certain conditions. In particular, the performance of the magnets when subjected to certain weights was evaluated to understand how the tangential stress value varied. The excellent results have shown that the chosen magnet models have a perfect resistance to the expected load stress and therefore, at a later time, have been applied on the inside of the fragments and then attached to the exhibition support. The restoration project was conceived with a view to minimal intervention and, at the same time, with the aim of giving a better usability of the work.