论文信息 - The Santi Quattro Coronati by Nanni di Banco: cleaning of the gilded decorations

The Santi Quattro Coronati by Nanni di Banco: cleaning of the gilded decorations

Abstract An optimised laser methodology was devised to clean gilded decorations found on the hair and robes of the Santi Quattro Coronati , marble sculptures by Nanni di Banco. The optimisation of laser parameters was achieved through comparative cleaning tests by employing Nd:YAG (1064 nm) and Nd:YAP (1340 nm) laser systems. The different cleaning results were characterised by microscopy, spectral reflectometry, and FT-IR analyses. In particular, high removal control was achieved using short free running (SFR) Nd:YAP and Nd:YAG lasers that allowed gradual cleaning levels. Conversely, a single cleaning level was possible using a Q-switching Nd:YAG laser, which also induced an undesired yellowish-orange appearance of the cleaned surface. Following the analysis of these results, the whole cleaning treatment of gilded areas was performed using SFR Nd:YAG laser.

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