Diagnostics pre and post Conservation on a 14th Century Gilded Icon from Taormina, Sicily

This paper reports on the pre and post conservation diagnostics of a 14 th century icon, the Virgin with the Child and a Saint, by an unknown author, belonging to the Library of Taormina, Sicily. A set of non­invasive imaging techniques for the investigation of the small painting was applied before and after the restoration treatment. The methods used included technical photography (UV Fluorescence, UV Reflected, Infrared, Infrared False Color, and Infrared Fluorescence), Infrared Reflectography (IRR), Reflectance Transformation Imaging (RTI) and two spectroscopic imaging techniques, Terahertz Time Domain Imaging (THz­TDI) and Reflectance Imaging spectroscopy using a Multispectral Imaging system (MSI). At the end of the investigation, an identification of the palette has been attempted, crossing the results obtained by reflectance spectra analysis with those obtained by the other imaging techniques. THz­TDI examination gave a substantial contribution to the understanding of the gilding technique. An accurate examination of the surface has been performed with Reflectance Transformation Imaging (RTI) and with THz­TDI to locate cracks, flacking, incisions and material losses. Subsurface layers have been tested by THz­TDI, imaging the support­primer­ paint interfaces. This study is a valid example of the application of non­invasive imaging methods before and after the conservation treatment of a work of art. of multi­technique approach to identify