Assessment of consolidants for the preservation of Tituli Picti on amphorae from the Ses Fontanelles late Roman shipwreck (Mallorca, Spain): An analytical approach

Abstract

The ceramic materials from the Ses Fontanelles wreck are an exceptional find due to the large number of amphorae with preserved inscriptions and their state of preservation. The presence of Tituli Picti is uncommon, and even less so in ceramics altered in an underwater environment. The bibliography on the conservation of these elements is scarce. This manuscript presents the results of a comparative study of two consolidation products: one based on nanoparticles (Nano Estel 1:1) and the other on an acrylic resin based on organic solvents (Paraloid B72 3 % in acetone).This preliminary study aims to establish a methodology for the treatment of the inscriptions painted on Roman amphorae from the Ses Fontanelles wreck (Mallorca), 4th century AD. A suite of analytical techniques was employed, encompassing surface analysis via Scanning Electron Microscopy - Energy Dispersive X-Ray Spectroscopy (SEM-EDX), X-Ray Diffraction (XRD) for the identification of crystalline phases, hardness and micro-indentation testing, peeling test, and measurements of aesthetic alterations using a spectrophotometer and glossmeter. The results obtained from these analyses were found to be highly congruent, underscoring the effectiveness of a long-standing acrylic resin and the potential of the silica nanoparticle-based product, which has seen a surge in utilization. This study also paves the way for further research in this area, as it opens up new avenues for exploration and the potential discovery of additional findings.