Surface enhanced Raman scattering of inorganic microcrystalline art pigments for systematic cultural heritage studies.

The present work summarizes our experimental data on Surface-enhanced Raman scattering (SERS) of inorganic pigments. The effect of pigment type on Raman scattering enhancement was studied. The paper also describes the features of the SERS-active substrates used as well as the methods of sample preparation for SERS analysis of the pigments. The results of successful application of SERS and micro-SERS for art pigments identification in the canvas paintings and icons have been demonstrated. The techniques allowed us to clearly identify the composition of blue and green paint layers as well as grounds in the nine artworks. This lead to determination of the lower time limit of work creation, to dating of the restoration interventions, to distinguish red ochers from two different deposit sources of raw mineral. The enhancement of Raman scattering intensities allows to reduce significantly the amount of the sample being taken from artwork (up to 1 μg).