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This paper presents the results obtained from the thermal analysis of a set of geomaterials (clays, pyroclastic materials, and industrial recycled materials) to be used as raw materials for the synthesis of geopolymers, specifically designed for the conservation of Cultural Heritage (CH) buildings, particularly in seismic hazard zones such as Sicily. X-ray diffraction and gas volumetric analysis (calcimetry) were applied to this set of raw materials in order to characterize the materials from the chemical and structural point of view. Thermogravimetric analysis (TG), TG coupled to Fourier transform infrared spectroscopy (TG-FTIR), and differential scanning calorimetry were used to characterize their thermal behavior. The statistical treatment of the thermogravimetric data by principal component analysis and hierarchical clustering analysis highlights the direct relation between the thermal data and the material composition that will be exploited for the selection of the best materials to obtain geopolymers specifically designed for the conservation of CH buildings.

Gandharan art developed in the Himalayan area in the early centuries CE. It has been investigated mostly from an iconographic point of view, missing, until very recently, a systematic technical investigation of materials and techniques. Recently our team began performing chemical analyses of the traces of the polychromy originally covering statues, reliefs and architectural decorations, to discover the ancient painting techniques and artistic technologies. This paper presents the results of the analytical investigation (optical microscopy, Raman spectroscopy and gas chromatography coupled with mass spectrometry) of pigments, ground layers and binders of a new group of samples taken from stucco architectural decorations (2nd–3rd/4th centuries CE). The samples were collected directly at an archaeological site in the Swat Valley, ensuring the exact knowledge of their stratigraphic provenance, as well as the absence of any restoration treatment applied prior sampling. The results are discussed in the wider context of Gandharan polychromy investigated so far by our team, as found in sculptures and architectural decorations preserved in museums (in Italy and France) and in archaeological excavations in Pakistan. The aim of this research is to shed light on the materials and techniques of this Buddhist ancient art from this region and on the influences exerted on it from Eastern and Western artistic traditions.

Green pigments in micro-samples taken from three late-medieval painted objects from Norwegian churches have been investigated with the aim to characterize their constituents and understand how they relate to damages observed in passages containing green paints. The cross-sections were analyzed by optical microscopy under visible and UV light, Scanning Electron Microscopy coupled with Energy Dispersive X-Ray Spectrometry and vibrational spectroscopies (Raman, ATR-FTIR). In addition, Gas Chromatography coupled with Mass Spectrometry was employed for the characterization of binding media, using a derivatization methodology recently developed for the detection of metal soaps in paint samples. This extensive characterization aided the identification of the individual constituents and the stratigraphy of green paints. It also builds the foundation for future ageing studies that can provide better insights into the mechanisms of the processes at stake in selective delamination of paints containing copper complexes.

Metal soaps and resinates are known to be spontaneously formed in artistic paintings, as a product of the reaction between aliphatic and terpenoid acids released by hydrolysis and oxidation of the organic media and certain cations contained in some inorganic pigments. In this paper we present an optimization and the validation of a GC/MS method for the qualitative and quantitative analysis of mixtures of terpenoid acids and aliphatic mono and dicarboxylic acids and metal carboxylates of terpenoid and aliphatic mono and dicarboxylic acids in the same paint microsample. This is based on a two-step analytical approach entailing the subsequent use of two silylating agents, N,O-bis(trimethylsilyl)trifluoroacetamide for the analysis of free acids and metal carboxylates, and 1,1,1,3,3,3-hexamethyldisilazane for the analysis of free acids. The application of this approach is possible because of the good stability at room temperature of the TMS derivatives of aliphatic and terpenoid species, characterized by high boiling points and relatively low vapour pressures. The method was then applied to the characterization of samples collected from two reference paint layers aged for 20 years, a paint sample taken from a pulpit, and sample of the varnish coating of a wooden writing desk, both from the second half of the seventeenth century.

ConspectusThe 20th and 21st century oil paintings are presenting a range of challenging conservation problems that can be distinctly different from those noted in paintings from previous centuries. These include the formation of vulnerable surface “skins” of medium and exudates on paint surfaces, efflorescence, unpredictable water and solvent sensitivity, and incidence of paint dripping which can occur within a few years after the paintings were completed.Physicochemical studies of modern oil paints and paintings in recent years have identified a range of possible causal factors for the noted sensitivity of painting surfaces to water and protic solvents, including the formation of water-soluble inorganic salts and/or the accumulation of diacids at the paint surface, which are oxidation products of the oil binder. Other studies have investigated the relationship between water sensitivity and the degree of hydrolysis of the binder, the proportions of free fatty and dicarboxylic acids formed, as well as the relative content of free metal soaps. Thus far, data indicate that the qualitative and quantitative composition of the nonpolymerized fractions of the oil binder cannot be solely or directly related to the solvent sensitivity of the paint film. Conclusions therefore indicate that the polymeric network, formed upon the curing of the oil, plays a fundamental role, suggesting that water sensitivity, at least in some cases, may be related to the poor development and/or polar nature of the formed polymeric network rather than the composition of the nonpolymerized fractions.Poorly developed polymeric networks, in combination with the migration of polar fractions, i.e., dicarboxylic and hydroxylated fatty acids toward the paint surface, can be related to other degradation phenomena, including the separation and migration of the paint binder which can lead to the presence of observable skins of medium as well as the more alarming phenomenon of liquefying or dripping oil paints. It is thus crucial to understand the molecular composition of these paints and their physicochemical behavior to aid the further development of appropriate conservation and preservation strategies, as the risks currently associated with surface cleaning treatments and other conservation procedures can be unacceptably high.This Account reviews the relationships between the degradation phenomena associated with modern oil paintings and the chemical composition of the oil binder and proposes a molecular model for the development of water sensitivity and other noted degradation phenomena. It is suggested that water sensitivity (and possibly other degradation phenomena) is a consequence of processes that take place upon curing, and in particular to the rate of formation and decomposition of alkoxyl and peroxyl radicals. These reactions are strongly dependent on the type of oil present, the ambient environmental conditions, and the chemical and physical nature of the pigments and additives present in the paint formulation. When the curing environment is oxidizing, the chemistry of peroxyl radicals dominates the reaction pathways, and oxidative decomposition of the paint film overwhelms cross-linking reactions.

In this paper we present a new analytical GC/MS method for the analysis of mixtures of free fatty acids and metal soaps in paint samples. This approach is based on the use of two different silylating agents: N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) and 1,1,1,3,3,3-hexamethyldisilazane (HMDS). Our experimentation demonstrated that HMDS does not silylate fatty acid carboxylates, so it can be used for the selective derivatization and GC/MS quantitative analysis of free fatty acids. On the other hand BSTFA is able to silylate both free fatty acids and fatty acids carboxylates. The reaction conditions for the derivatization of carboxylates with BSTFA were thus optimized with a full factorial 32 experimental design using lead stearate and lead palmitate as model systems. The analytical method was validated following the ICH guidelines. The method allows the qualitative and quantitative analysis of fatty acid carboxylates of sodium, calcium, magnesium, aluminium, manganese, cobalt, copper, zinc, cadmium, and lead and of lead azelate. In order to exploit the performances of the new analytical method, samples collected from two reference paint layers, from a gilded 16th century marble sculpture, and from a paint tube belonging to the atelier of Edvard Munch, used in the last period of his life (1916–1944), were characterized.

The most common synthetic carbon-based black pigments can be divided into three main groups on the basis of the material used for their production: bone blacks, vine blacks and lampblacks. This work reports on the physicochemical characterization of the three commercial pigments purchased from Kremer Pigmente (Germany) and Zecchi (Italy) by means of a multi-analytical approach, which included thermoanalytical (thermogravimetry, thermogravimetry coupled with FTIR and differential scanning calorimetry) and spectroscopic techniques (laser-induced breakdown spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy and X-ray powder diffraction). Combining the results obtained from this multi-analytical approach, qualitative and quantitative conclusions are drawn for the first time. Lampblacks are mainly composed of amorphous carbon. In vine black (Kremer), amorphous carbon and cellulose pyrolysis by-products are the main constituents. In bone blacks and vine black (Zecchi), carbonaceous materials are minor components. Hydroxyapatite and calcium carbonate are the main constituents of bone blacks, and iron and magnesium oxides are the main constituents of vine black (Zecchi). Results from this multi-analytical study on the composition of such widespread pigments can provide valuable information in the decision-making process for restorers and conservators.

A series of Burmese lacquered objects decorated with the yun (incised) technique and belonging to the British Museum’s collection was analysed with the aim to investigate the decorative materials—lacquer, binding media, additives and pigments—used in the production of these objects, which span chronologically from the eighteenth century to the late twentieth century. As the manufacturing process is supposed to have remained very similar over this time period, especially regarding the use of materials, we were interested in scientifically assessing for the first time the nature of these materials and the correspondence to the written sources in the relation to their specific use. Gas chromatography mass spectrometry (GC–MS) and analytical pyrolysis with in situ silylation coupled with GC–MS (Py(HMDS)GC–MS) were used for the identification of the organic components in several samples taken from the coloured areas of the objects. Fibre optic reflectance (FORS) and Raman spectroscopies were used to identify the pigments after a visual investigation of the samples by digital microscopy. Burmese lacquer was detected in all objects and trends in its degradation were highlighted. Lipids, proteins and saccharide material were found to be mixed with lacquer, and they appeared to be applied with specific pigments, in good agreement with the written records, apart from proteins, which are not mentioned. The use of synthetic pigments, such as phthalocyanines blue and green and chrome yellow, was assessed in the most recent objects, showing an evolution in the use of pigments. Indigo, although expected, was not identified in any of the green samples and Prussian blue appeared to be the main source of blue colour. All this information is of fundamental importance for conservation practices and corrects the general opinion about the production materials of these objects. These results also open the way to future research dedicated to exploring the chemical interaction between Burmese lacquer, proteins, lipids, gums and pigments, with the aim to predict possible differences in degradation pathways.

Identification of proteins in paintings and polychrome objects is a challenge, which requires the development of tailored analytical approaches. In the present study, a targeted proteomics approach was developed for discriminating among the three most common proteinaceous materials used as paint binders, i.e. milk, egg, and animal glue. In this study a specific database of peptides was created based on tandem MS analyses of tryptic digests of several paint samples collected from a variety of art objects of different ages and conservation conditions. Specific peptide markers of each protein were then selected and monitored by LC-MSMS in Multiple Reaction Monitoring (MRM) ion mode, together with their specific precursor ion-product ion transitions, as defined by their unique amino acid sequence. The developed method enabled a sensitive and reliable detection of the target peptides in a selection of case studies, leading to the unambiguous identification of the proteins used as paint binders. The method showed greatly increased sensitivity compared to currently available strategies.

Since the introduction of the term ‘geopolymer’ by Davidovits in 1978, many works have been published, sometimes providing clear and concise indications, and other times creating confusion about what are a geopolymer. What seems interesting beyond the terminology discourse is the advantage of low CO2 emissions, the use of waste industrial byproducts in their implementation and the resistance to air pollution and aggressive agents. Playing on the combination of the different precursors and alkaline activators, geopolymers can reach competitive mechanical properties and significant environmental benefits. The materials, with specially designed formulations, can be fireproof, breathable, resistant to rising salts and acid rain, as well as products with low emission of carbon dioxide. Furthermore, a further advantage is the ability to imitate natural, artificial and stone materials. There are hundreds of papers about characteristics, properties both of precursors and final product, but only a few of them about the Cultural Heritage Application. Despite this, the data shown by the few publications present to date give hope for a use of these materials for the consolidation, conservation and restoration of the heritage built within the historical centres, where the low CO2 emissions and the characteristics shown by the geopolymers could bring a huge benefit to the environment and the protection of the structures themselves. In this work, we briefly review the bibliography available on the applications of these materials to Cultural Heritage, hypothesising future uses aimed at specific urban contexts, where the application could play a key role in the future projects to restore the built heritage.

Understanding the original techniques in the creation of an artwork is a prerequisite for the selection of the most appropriate conservation method. This is particularly essential in wall paintings where control of potential agents of deterioration and efficient monitoring are limited due to the scale of the paintings and their exposure to uncontrollable environmental fluctuations. Analytical studies are increasingly focused on the investigation and study of degradation products of organic binders originally added in the paintings on a lime-based plaster ground. In the framework of IPERION-CH (Integrated Platform for the European Research Infrastructure ON Cultural Heritage) project, a collaborative task is dedicated to obtain knowledge about original organic materials used in wall paintings by evaluating and comparing different innovative methodologies and conventional diagnostic techniques used for the investigation of markers related to alteration mechanisms and degradation products. The non-invasive and microsampling methodology is first optimized on well-defined models that have been designed to simulate different painting techniques with limewater and five organic binders in different relative proportions. Future investigations will focus on the application of the optimized methodology on archaeological samples. In the present paper, preliminary results on a selected set of models, submitted in different stages of a well-established artificial ageing protocol, demonstrate the specific complementary input of each analytical technique included in the analytical approach (colour measurements, micro FTIR-ATR analyses in cross-sections, Evolved Gas Analysis-Mass Spectrometry and Gas Chromatography-Mass Spectrometry). The comparative evaluation and interpretation of the results is a step forward in the optimization of the approach and in relating the analytical findings detected on the analysed samples to the original compounds and the possible changes for each group of binders (proteins/gums) due to degradation or interaction depending on the pigment/metal ion present.

open 17 si The composition of the ancient wax-based painting technique known as encaustic has long been the subject of debate. Ancient sources provide few details of the technology, and modern understanding of the medium is restricted to theoretical interpretation and experimental observation. In this multi-analytical collaborative study, a number of analytical approaches were used to investigate the physical and molecular properties of a range of experimentally prepared encaustic paints before and after ageing. Analysis using gas chromatography mass spectrometry, Fourier transform infrared spectroscopy (invasive and non-invasive), X-ray diffraction and thermogravimetric analysis demonstrated how differences in the technology of production alter the properties and composition of the medium and showed how these are modified by the addition of pigment and the effects of ageing. Comparison of results from the different analytical techniques highlights the benefit of an integrated analytical approach to the analysis of ancient encaustic paints and the fundamental importance of insights from invasive study to evaluating the results of non-invasive analysis. open Stacey, R.J.*; Dyer, J.; Mussell, C.; Lluveras-Tenorio, A.; Colombini, M.P.; Duce, Celia; La Nasa, Jacopo; Cantisani, Emma; Prati, S.; Sciutto, G.; Mazzeo, R.; Sotiropoulou, S.; Rosi, F.; Miliani, C.; Cartechini, L.; Mazurek, J.; Schilling, M. Stacey, R.J.*; Dyer, J.; Mussell, C.; Lluveras-Tenorio, A.; Colombini, M.P.; Duce, Celia; La Nasa, Jacopo; Cantisani, Emma; Prati, S.; Sciutto, G.; Mazzeo, R.; Sotiropoulou, S.; Rosi, F.; Miliani, C.; Cartechini, L.; Mazurek, J.; Schilling, M.

This work proposes a multi-analytical approach to determine the additives in historical mortars, the use of which is widely described in bibliographical sources, but has rarely been reported in the literature. A protocol to thoroughly analyse mortars was created (optical microscopy, X-ray diffraction, infrared spectroscopy, thermal analyses and gas chromatography – mass spectrometry). These techniques had already been carried out on samples from various sites from the Roman to the modern era, finding that additives had only been used in the mortars from the internal masonry at our sampling site: the medieval military shipyard of Amalfi (Italy). The investigations yielded information on the production technology, and FT–IR and GC–MS revealed a saccharide material-based additive in the mortars, of plant origin. The FT–IR spectra suggested the presence of a natural gum, which has been used since ancient times to strengthen the cohesion properties of mortars and their resistance to tensile stress

This volume inaugurates a series of publications aiming to disseminate the research outputs arising from the CNR-CACH Bilateral Agreement of Scientific and Technological Cooperation - focusing on cultural heritage conservation, valorization and management - signed in November 2014, between the National Research Council of Italy and the Chinese Academy of Cultural Heritage. This first volume collects some of the papers presented during the international conferences organized by the two Institutions, respectively in Rome on November 2014 and in Dazu on June 2015, when exploring their respective fields of interest and expertise. The following three volumes will be dedicated to the results of the three bilateral research projects financed under the mentioned Agreement and undertaken in the period 2016-2019.

A chemical investigation of the organic paint binders of the Giant Buddhas of Bāmiyān was performed using an analytical approach based on mass spectrometry, combining traditional gas chromatography/mass spectrometry protocols with advanced proteomics methodologies. The research was carried out on a selection of rescued fragments. The data revealed the use of egg proteins as the paint binders of the original layers, in accordance with the traditional use of this proteinaceous medium in antiquity, spanning from the Mediterranean basin to the Far East, and already in the Bronze Age. Egg tempera was thus known to artists of the region in the first centuries AD, probably also due to the position of the Bāmiyān valley, which was connected to the Silk Road. Milk was found in the first historical overpaintings. A new proteomics approach was used, which was able to identify the source of the milk proteins present in the restoration layers, despite their age and degradation. In particular cow's and goat's milk were both found, in agreement with the documented presence of rich pastures in the Bāmiyān valley when the historical restorations were carried out. Investigating the materials of the Giant Buddhas not only enabled us to obtain isolated data on these invaluable works of art, which are now lost, but contributes to understanding the big ªpuzzleº of our past and the development of our culture, by implementing and supporting written sources, stylistic and anthropological studies with molecular data.

Eosin is a xanthenic synthetic organic dye/pigment synthesized by Caro in 1873. It was precipitated with lead and aluminum salts and commercialized as geranium lake and it was one of the most brilliant hues in the palette of the Impressionist painter Vincent van Gogh. Unfortunately, the high photosensitivity of eosin has caused the evident fading of the intense pink colorations of his canvas paintings into lighter ones. This work aims at underlying the contribution of several complementary different analytical techniques in disclosing a very complex and still little-known topic such as the degradation process of eosin.

This paper describes a method for reliably identifying saccharide materials in paintings. Since the 3(rd) millennium B.C., polysaccharide materials such as plant gums, sugar, flour, and honey were used as binding media and sizing agents in paintings, illuminated manuscripts, and polychrome objects. Although it has been reported that plant gums have a stable composition, their identification in paint samples is often doubtful and rarely discussed. Our research was carried out independently at two different laboratories: the Getty Conservation Institute in Los Angeles, USA (GCI) and the Department of Chemistry and Industrial Chemistry of the University of Pisa, Italy (DCCI). It was shown in a previous stage of this research that the two methods give highly comparable data when analysing both reference paint samples and paint layers from art objects, thus the combined data was used to build a large database. In this study, the simultaneous presence of proteinaceous binders and pigments in fresh and artificially aged paint replicas was investigated, and it highlighted how these can affect the sugar profile of arabic, tragacanth, and fruit tree gums. The environmental contamination due to sugars from various plant tissues is also discussed. The results allowed the development of a new model for the reliable identification of saccharide binders in paintings based on the evaluation of markers that are stable to ageing and unaffected by pigments. This new model was applied to the sugar profiles obtained from the analysis of a large number of samples from murals, easel paintings, manuscripts, and polychrome objects from different geographical areas and dating from the 13(th) century BC to the 20(th) century AD, thus demonstrating its reliability.

Background Establishing the distribution of materials in paintings and that of their degradation products by imaging techniques is fundamental to understand the painting technique and can improve our knowledge on the conservation status of the painting. The combined use of chromatographic-mass spectrometric techniques, such as GC/MS or Py/GC/MS, and the chemical mapping of functional groups by imaging SR FTIR in transmission mode on thin sections and SR XRD line scans will be presented as a suitable approach to have a detailed characterisation of the materials in a paint sample, assuring their localisation in the sample build-up. This analytical approach has been used to study samples from Catalan paintings by Josep Maria Sert y Badía (20th century), a muralist achieving international recognition whose canvases adorned international buildings. Results The pigments used by the painter as well as the organic materials used as binders and varnishes could be identified by means of conventional techniques. The distribution of these materials by means of Synchrotron Radiation based techniques allowed to establish the mixtures used by the painter depending on the purpose. Conclusions Results show the suitability of the combined use of SR μFTIR and SR μXRD mapping and conventional techniques to unequivocally identify all the materials present in the sample and their localization in the sample build-up. This kind of approach becomes indispensable to solve the challenge of micro heterogeneous samples. The complementary interpretation of the data obtained with all the different techniques allowed the characterization of both organic and inorganic materials in the samples layer by layer as well as to establish the painting techniques used by Sert in the works-of-art under study.

An organic binder was identified in the painted fragments from the Canaanite palace of Tel Kabri, Israel. Recently dated to the late 18th century B.C.E. by 14 C, Tel Kabri is the most ancient of the Eastern Mediterranean sites in which Aegean style paintings have been found. The application of pigments was suspected to be using an organic binding medium, particularly for the Egyptian Blue pigment. Samples of blue paint were examined using evolved gas analysis-mass spectrometry (EGA-MS) in order to overcome the analytical challenges imposed by highly degraded aged proteinaceous materials. Egg was identified as the binder based on the presence of hexadecanonitrile and octadecanonitrile, confirming the use of a secco painting technique. Lysozyme C from Gallus gallus was detected by proteomics analysis, confirming the presence of egg. To our knowledge, this is the earliest use of egg as a binder in Aegean style wall paintings.

A unique sample of ink from an inkwell in the Schoyen Collection allegedly found at Qumran has been subjected to analyses by several analytical techniques: GC-MS, proteomic analysis, PXRD, Raman, (ATR) FT-IR, LIBS, ICP-MS and MS. The results reveal to an unexpected level of detail how the ink was manufactured, which gives insight into, the industrial processes and craftsmanship that were practiced at the Qumran settlement during the Second Temple period (100 BCE-CE 70). The identified minerals and other organic and inorganic materials are sufficiently multiple and diverse that it is probable that this specific ink can be recognized if analyses. of inks are performed on manuscripts from Qumran and other locations in Israel and the Middle East. The present work exposes a distinct and unique possibility to shed light on early Jewish manuscript controversies, including their provenance. (C) 2012 Elsevier Ltd. All rights reserved.