Monitoraggio delle applicazioni laser nel restauro dei frammenti di sectilia in pasta vitrea dagli scavi della villa tardoantica di Aiano-Torraccia di Chiusi

Cavalieri, Marco [UCL] et al.

The discovery of more than 1600 glass sectilia during the archaeological excavations on the Roman villa in Aiano (IV - V century BC) has required the definition of punctual strategies to gather, catalogue and restore the fragments. After dusting the surfaces, the conservation and the morphology of fragments have been examined; chemical and physical analysis also helped to detect matters and procedures. Careful tests have been then made in order to identify the best methods to remove any residues due to burial; laser ablation has been identified as the most efficient and respectful of the brittle glass surface. The cleaning has been made via a double emission - Q-Switch (pulse duration 15 ns, energy from 10 mJ to 140 mJ) and Short Free Running (pulse duration from 30 to 100 µs, energy from 100 mJ to 1 J) laser – continuously verifying the results through Dino Lite Digital and Digital 3D Microscopy. Scanning Electron Microscopy (SEM) has been also used to investigate glass composition and structure, as well as to check the effects of the laser ablation on the original surfaces.