Identification of Inorganic Pigments Used in Porcelain Cards Based on Fusing Raman and X-ray Fluorescence (XRF) Data

Abstract

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.

Microanalysis of clay‐based pigments in painted artworks by the means of Raman spectroscopy

“…It is principally caused by their easy use, non‐destructivity and a broad range of applications, which encompasses both organic and inorganic substances. Raman spectroscopy is a sought–after method thanks to its availability, relatively low cost of instruments and systematic development of new measurement techniques . However, its serious drawback still lies in the formation of undesirable fluorescence, which is an accompanying phenomenon of measurements of various materials and which is hard to predict.…”

An overview of Principal Components Analysis approaches in Raman studies of cultural heritage materials

“…Similarly, Deneckere et al 43 applied PCA on a fused dataset comprising Raman spectra acquired on 24 natural and synthetic inorganic pigments, and on a polychrome object, a porcelain card and the corresponding elemental information (areas obtained from micro‐XRF spectra). Raman spectra were acquired with both a 785‐ and a 532‐nm laser, the former being generally able to provide good quality spectra for identification purposes.…”

Mobile Spectroscopic Instrumentation in Archaeometry Research

“…[13][14][15][16] A similar approach was used for the analysis of 19th century porcelain cards that were positioned under the Raman microscope. 17,18 The difference between the two strategies is that in the first case the instrument was transported to the museum, while in the latter case the artifacts were brought into the laboratory. Apart from the possible cumbersome transport of sensitive scientific equipment, proper room darkening in the location where the analysis takes place is essential: ambient light can overwhelm the Raman signal.…”