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Fourier transform infrared (FT‐IR) and Raman spectroscopy is used for the non‐destructive analysis of painting materials and ageing compounds in micrometric cross sections of a glass painting. The combination of both techniques in conjunction with imaging/mapping function provides the spatial distribution of chemical components identified in vibrational spectra. The aim of our work is to show the applicability of the FT‐Raman mapping technique in the detection of painting materials. We also compare Raman information gained by using two laser excitations at 532 and 1064 nm implemented in microspectrometers with different confocality and spatial resolution. In turn among FT‐IR imaging techniques, we compare chemical images recorded in external reflection and attenuated total reflection modes that give chemical images of different size and spatial resolution. Our FT‐IR and Raman imaging characterize a number of painting materials such as pigments, binders, fillers as well as degradation products. Raman maps are constructed by using the univariate analysis. In turn, a profile of IR images requires the use of a more complex methodology. Here, we compare FT‐IR images of the painting cross sections obtained by using the univariate and hierarchical cluster analysis. We clearly show that the multivariate approach is a powerful tool for the credible construction of IR images, providing the relevant chemical information on the multicomponent stratigraphy of the samples. Moreover, the combination of all the methods allows us to demonstrate their degree of utility for the study on the paint cross sections of the works of art. Copyright © 2013 John Wiley & Sons, Ltd.

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Laboratory X-ray powder diffraction was used to investigate mineralogical compositions of green pigments labeled by suppliers as “green earths.” It was found that glauconite and celadonite—minerals historically considered as the main ingredient of this pigment—were present only in Bohemian green earth, green earth from Thuringen (glauconite), and Bavarian green earth (celadonite). Other investigated pigments consist of mineralogical-component minerals with added synthetic organic colorants. The obtained results may be useful for scientists, restorers, and artists in proper choices of the pigments they use in their works.

The aim of this study is to estimate changes of color of wall paintings under the influence of one of the basic conservation procedures, that is, paint layer consolidation due to degradation of the original binder. Since the 1960s, wall paintings have been consolidated almost routinely with synthetic polymers. As the research on the subject progressed, many flaws of these products were observed. Extensive research was conducted with the aim of determining the actual impact of synthetic binders on paint layer properties. The article discusses the results from only one group of tests associated with color change measurements. Three painting techniques were selected for the study, representing a variety of original techniques common in Poland: lime, lime casein, and animal glue, as well as five commercial synthetic products predominantly employed for painting consolidation by the Polish conservation community.We are focusing on color changes taking place as a result of consolidation and subsequent from the progress of degradation. K E Y W O R D Scolor difference,

Artykuł opisuje jeden z podstawowych zabiegów konserwatorskich, tj. utrwalanie malowideł ściennych, zwane również konsolidacją warstw malarskich. W polskiej praktyce konserwatorskiej zabieg wykonywany niemal rutynowo przy użyciu różnych środków klejących. Prawie trzy czwarte z przeanalizowanych przypadków dotyczy zastosowania żywic syntetycznych w postaci roztworów o niskich stężeniach lub dyspersji. Przeprowadzono badania mające na celu określenie ich wpływu na istotne właściwości mechaniczne warstwy malarskiej takie jak: twardość, moduł Younga, kohezja, adhezja do podłoża, a także ścieralność. Zastosowano nowoczesne techniki mikroindentacji instrumentalnej oraz tradycyjną metodę przecierania powłoki za pomocą strumienia materiału ściernego. Do badań wytypowano trzy techniki malarskie powszechne wśród zabytkowych malowideł ściennych w Polsce: wapienną, kazeiny wapiennej i klejową, a także pięć gotowych preparatów, najczęściej wykorzystywanych przez polskie środowisko konserwatorskie w 2 poł. XX w.