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Raman spectroscopy, being a laser spectroscopic method, is gaining increasingly more interest for applications in the field of art and archaeology. The technique is especially appreciated for its non-destructive character, the speed of analysis and the ability to obtain molecular information on a whole range of materials, organic as well as inorganic. Although the Raman effect was observed for the first time in 1928, it was not until the end of the 1980s before instrumental improvements enabled the analysis of micro-samples, and thus allowing the application of this method in archaeometry.

A study of the pigments of “The Ecstasy of St. Theresa,” a seventeenth century oil painting on canvas, was performed by Raman microscopy. Lazurite was identified in both Jesus Christ’s and St. Theresa’s mantles as the pigment responsible for the blue coloration. Litharge was identified inside the black bitumen layer. Usually the bitumen needed a lot of time to dry in the air when mixed with drying oil. Litharge was used by the artist to decrease the oil drying time. A complementary study, using micro-Raman and SEM, allowed us to identify red ochre as the pigment responsible for the red coloration in the altar on the left side of the painting.

A study of the pigments of “The Ecstasy of St. Theresa,” a seventeenth century oil painting on canvas, was performed by Raman microscopy. Lazurite was identified in both Jesus Christ’s and St. Theresa’s mantles as the pigment responsible for the blue coloration. Litharge was identified inside the black bitumen layer. Usually the bitumen needed a lot of time to dry in the air when mixed with drying oil. Litharge was used by the artist to decrease the oil drying time. A complementary study, using micro-Raman and SEM, allowed us to identify red ochre as the pigment responsible for the red coloration in the altar on the left side of the painting.

Measurements aimed at optical characteristics of the basic building material of the Renaissance dome of King Sigismund’s Chapel in Wawel Castle are described in the paper. Colorimetric measurements, LIBS investigations and Raman effect measurements were carried out. LIBS spectra of encrusted and clean (fresh fractured) grey-greenish Myslenicki sandstone are presented. Raman spectra and reflection coefficients as well as L , a , b coordinates for several samples are also shown.

The fluorescence spectra of historical and model paper samples, previously irradiated with the laser beam at wavelengths of 1,064, 532, 355, and 266 nm, are recorded under excitation at 266 nm, and the nonirradiated samples are used for reference. The spectral profiles obtained for the laser-treated model papers made of cotton and/or linen only reveal differences compared to the reference ones. After irradiation at 532 and 1,064 nm, a decrease of the band intensities of the entire spectral profile is observed. In contrary, the UV irradiation at 355nm of the same samples results in the increase of bands centered at 341 and 370nm compared to the visible region only. Prolonged treatment at 266nm results in the marked increase of band intensities in the visible region and corresponds to the independently observed yellowing.

A parametric linear correlation method that enables the identification of the different elements in multicomponent LIBS spectra based on the comparison against reference spectra of individual elements is proposed. The method is described and preliminary tests are presented with spectral data obtained during the analysis of archaeological bronze.

A study on the painting materials (pigments and binders) of the famous painting “Madonna col Bambino e S. Giovannino” by Sandro Botticelli, located in the Museo Civico of Piacenza (Italy), was performed before a recent restoration. The painting materials were investigated by the analysis of five millimetric samples taken in damaged regions. The pigments were determined using the micro-Raman spectroscopy, with the 632.8nm line of a He–Ne laser. Despite the strong fluorescence background, the nature of the ground layer (gypsum and anhydrite) and of most pigments (i.e. goethite, lapis lazuli, white lead) was determined. Gas chromatography coupled with mass spectroscopy (GC/MS) was used to determine the organic binder media, and in particular proteinaceous and lipid materials. Egg and animal glue were found, while no siccative oils were detected.

Roman ceramics from different production areas have been analyzed by means of “laser induced plasma spectroscopy” (LIPS). The overall objective of this study is to show the capability of LIPS to classify these archaeological ceramics as a function of their provenance. The use of linear correlation methods allows us to cluster the samples by quantitative comparison of their LIP spectra, leading to a reliable assignment of Terra Sigillata pieces to their regions of origin and establishing reference groups for the purpose of assigning future pieces.

Laser-induced fluorescence of intrinsic fluorophores of organic media found in paintings (casein, animal glue and egg proteins) provides a means of characterising general classes of media depending on the amino acid composition and presence of degradation cross-linkages. Wavelength dependence of spectra is investigated for non-destructive and non-invasive analyses of thin films of protein-based binding media.

The importance of Raman micro-spectroscopy for the identification of pigments in works of art is well established. In recent times, portable Raman spectrometers have been introduced which allows users to perform field analysis directly where the artefacts are placed (churches, museums, archaeological sites, etc.). The present work reports results obtained by a remarkably compact instrument, in particular, on frescoes and illuminated parchments.