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This paper presents the results of analyses carried out on the paintings on the rock‐hewn walls of the Forty Martyrs church at Şahinefendi in Cappadocia (a UNESCO World Heritage Site), a central region of Turkey, performed during conservation work from 2007 to 2012. The micro‐samples were investigated by spectroscopic, micro‐stratigraphic and scanning electron microscopy analysis in order to study the painting technique, the materials and the degradation products. The micro‐stratigraphic analysis showed a white, sometimes pinkish, plaster. Micro‐Raman analysis, performed on cross‐sections of the mortars, enabled the detection of calcite, gypsum, anhydrite and calcium oxalate. Scanning electron microscopy and energy‐dispersive spectroscopy revealed a similar composition among all investigated phases, aside from minor differences such as the presence of diatoms in the second and third phases and of biotite, lime lumps and plants fragments in the fourth one. Apart from traditional pigments of medieval wall paintings, micro‐Raman analysis revealed the presence of lead‐based compounds and jarosite.

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This paper presents the results of analyses carried out on three decorative phases of the presbytery of the church of Santa Maria Antiqua al Foro Romano in Rome: the fourth‐century ad mosaics setting bed; the Adoration of the Cross, dated to the papacy of John VII (ad 705–7); and the paintings in the apse of the Pope Paul I (ad 757–68) phase. The research allowed the characterization of the painting techniques, pigments, organic compounds and degradation products by means of a video microscope, optical microscopy, and μ‐Raman and FT–IR spectroscopy, contributing to a better understanding of the changes in the techniques and materials used throughout the centuries in one of the most relevant medieval Christian monuments in Western Europe.

The present contribution focuses the attention on the mural paintings of two among the oldest Cappadocia churches, belonging to the group of “proto‐Byzantine paintings.” These materials have never been extensively investigated before and represent a starting point of paramount importance to understand the evolution of both materials and techniques during the ages in this extraordinary region of central Turkey. Specifically, among the several investigated churches and after the synergic work of art historians, conservators, and scientists, we selected the church of St. John the Baptist at Çavuşin, whose architectural structure is dated back to fifth–sixth century, and Church nr. 5 (Süslü church, sixth–ninth century) in Güllü Dere. A limited but exhaustive number of samples was carefully selected and then collected during the on‐site campaign in Cappadocia. Samples were investigated with a multianalytical approach by using cross‐section examination, X‐ray fluorescence spectroscopy (XRF), Fourier‐transform infrared (FT‐IR), and micro‐Raman spectroscopy to characterize materials, execution technique, and conservation state. The wall paintings in the church of St. John the Baptist are characterized by the presence of superimposed or adjacent layers ascribable to different historical periods, as it occurs in many of the Cappadocia churches. Their discrimination has been based on the mortar/ground layer. Pigments have been successfully identified and are mainly based on iron earths and ochres; the presence of gypsum and anhydrite, oxalates, and organic materials have been highlighted on the surface, thus suggesting alteration processes. The church nr. 5 at Güllü Dere shows a unique pictorial phase. Pigments are applied on a gypsum based ground layer and exhibit alteration patterns being made of lead based compounds, such as lead oxides and carbonates. A peculiarity of this church is the presence of anatase, detected in correspondence of red and yellow areas of the samples.