Raman spectroscopy and X-ray fluorescence (XRF) spectroscopy are often used as complementary techniques that are well suited for the analysis of art objects because both techniques are fast, sensitive, and noninvasive and measurements can take place in situ. In most of these studies, both techniques are used separately, in the sense that the spectra are evaluated independently and single conclusions are obtained, considering both results. This paper presents a data fusion procedure for Raman and XRF data for the characterization of pigments used in porcelain cards. For the classification of the analyzed points of the porcelain cards principal component analysis (PCA) was used. A first attempt was made to develop a new procedure for the identification of the pigments using a database containing the fused Raman–XRF data of 24 reference pigments. The results show that the classification based on the fused Raman–XRF data is significantly better than the classifications based on the Raman data or the XRF data separately.
Annelien Deneckere, Lieke de Vries, Bart Vekemans, Lien Van de Voorde, Freek Ariese, Laszlo Vincze, Luc Moens, and Peter Vandenabeele, "Identification of Inorganic Pigments Used in Porcelain Cards Based on Fusing Raman and X-ray Fluorescence (XRF) Data," Appl. Spectrosc. 65, 1281-1290 (2011)