Diagnostics and conservation of an archaeological ‘coin purse’from the Vesuvian area

The “coin purse” from the excavations of the Vesuvian area is an exceptionally valuable textile artefact, one of the few organic material artefacts that did not carbonize during the eruption of Vesuvius in 79 AD. The find was in a poor status of preservation due to a thick deposit of brownish-grey soil that entirely covered the surface and compacted the fibres. One of the openings showed remnants of bright green corrosion products coming from the metal objects inside. Preliminary investigations were carried out to understand the nature of the materials and the level of degradation by false-colour IR imaging, UV fluorescence, Scanning Electron Microscopy (SEM). Radiographic acquisitions were also conducted in order to study the characteristics of the purse and the metal coins inside. After the diagnostic phase, it was considered appropriate to proceed with the dry removal of soil deposits by micro vacuuming followed by laser ablation of the residual deposits firmly bound to the fabric. Finally, copper corrosion products were extracted via chemical methods.