Integrated methodology for the evaluation of cleaning effectiveness in two Russian icons (16th-17th centuries).

This article covers a methodology for evaluating the effectiveness of cleaning two Russian icons. The icons belong to a group of five from the same iconographic school, dating from the 16th to 17th centuries. An integrated and complementary approach to varnish and overpaint removal involved microscopic techniques (optical and scanning electron microscopy) and colorimetry (CIE L*a*b* system). The materials and techniques used in these icons have been characterized previously. Cleaning revealed extensive overpainting that had not only dramatically changed the original appearance, but also the meaning and attribution of one of the two icons. The analyses carried out were useful in determining the extent of the overpainting and led to a better assessment of the results and effectiveness of the restoration.

Integrated analytical study for the authentication of five Russian icons (XVI-XVII centuries).

This article presents an integrated approach for the authentication of five Russian icons through the study of their paint materials (elemental composition and stratigraphic mapping), state of conservation and artistic technique. The results of the applied analytical protocol, involving optical and scanning electron microscopy coupled with energy-dispersive X-ray spectrometry and Fourier transformed infrared spectroscopy/microspectroscopy, led to the conclusion that the five icons belong to the same group and iconographic school (from Northern Russia) and date from the end of the 16th century to the beginning of 17th century. Because of massive overpainting, the icons "suffered" a change in iconographic style and significance, and restoration treatment brought to light the original painting and its attribution. Identification of the composition of the original chromatic palette used by the iconographer, the stratigraphic mapping and the conservation state of the painting materials, along with the features of the original artistic technique, furnished key elements for the icons' authentication. Here, we present the first experimental data concerning the identification of the authentication characteristics, being part of a large project that has as its final aim the evaluation of the effectiveness and effects of the cleaning agent on the paint layers.