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This work used a multi-analytical approach to characterize two 19th century ambrotypes and was motivated by the lack of insight on these historical objects. Photographic imaging and optical microscopy (OM) were used to identify abrasions, cracks related to reticulation, tarnishing, and other aspects associated to production and degradation processes. With variable pressure scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (EDS) these processes were seen with great detail and further characterized. Elemental point analysis and elemental mapping showed that the photosensitive material used was silver iodide. Degradation compounds were found as silver and chlorine-containing compounds. In one of the items, the tarnishing area also contained redeposited silver in a ring-shape surrounding a nucleus rich in silver, copper, and sulfur, in addition to copper-based salts. EDS analyses also identified that the supports were common soda–lime–silica glasses, refined with arsenic; and showed that a pigment rich in iron was used in both items to hand color the cheeks, extended with aluminum silicates alone or mixed with barium sulfate. Theμ-Raman study pointed out that a synthetic Mars pigment was employed.μ-Fourier-transform infrared spectroscopy analyses identified collodion as the binder. Shellac was used as a protective varnish in one of the items and a gum was possibly employed on the other. Bitumen was used for the background in one ambrotype.

The aim of this research was to characterize ten Provisini, one of the most common silver coins in the Middle Age, dating back to the 13th century A.D. These coins are composed by Ag-Cu alloy and were coined in the Roman mint. A non-destructive, micro-destructive and multi-analytical approach was used, aiming to preserve the surfaces of the coins. The results of XRD and micro-Raman spectroscopy allow defining the alloy composition and the mineralogical nature of the alteration products (e.g. cuprite, tenorite, chlorargyrite, stromeyerite). X-ray maps provided information on major elements distribution on the surface. Finally, Electrochemical Impedance Spectroscopy (EIS) and Voltammetry of Immobilized Micro-Particles (VIMP) permitted to reconstruct the possible scheme of the multi-layering of the patina on the coins. Then, the conservation status was monitored.

This paper is a preliminary study on the origin of the precious red pigment cinnabar by μ-Raman analysis. The importance of this pigment is partly due to its low availability. When the mineral was used in the Roman Age, the district of Almaden, Spain, was probably the most exploited region. However, it is still not well defined if further ores were chosen for supply. A scientific methodology has to be assessed. In the present study, samples with known provenance (Spain, Slovenia, Italy, Russia, China, and minor European deposits) were collected from Italian Mineralogical and Earth Science Museums. μ-Raman analysis was chosen to acquire structural data, which were finally treated by statistical analysis. Most of the samples from China were characterized by the presence of selenium. This was proved by the additional band at ~200 cm−1. The statistical analysis of Raman data suggests that the position of the most intense band at ~252 cm−1 also influences the discrimination of the Chinese samples. This work also demonstrates that a higher purity may be revealed by μ-Raman analysis, eventually leading to the discrimination of natural sources from synthetic cinnabar. It also proves that the most common exploitation sites, Almaden and Idrija, may be statistically distinguished. Despite its exploratory nature, this study is intended as a successful preliminary step to gain information of provenance from a single, potentially non-destructive technique, such as μ-Raman spectroscopy.

In this work it is reported for the first time the characterization of microplastics from sea water samples and in two congener species of seabreams: Pagellus erythrinus and P. bogaraveo, Mediterranean fish species of great commercial importance. An experimental survey was conducted on May-June 2017 in the southernmost part of the Tyrrhenian Sea. Microplastics found in the sea water and in the grastrointestinal tract of two teleosts were characterized by Raman and IR spectroscopies. Microplastics found in sea water samples appeared in the form of fragments made of plastics of low and high density (PVC and LPDE). All the microplastics found in fish belonged to Nylon 66, typical fibers used in industry and in fisheries. Our findings highlighted the importance of further studies along the food web chain for a better understanding of the diffusion and possible consequences of this terrible threat.

Gregório Lopes (1490-1550) foi um dos pintores mais proeminentes do Renascimento e Maneirismo Português. A pintura “Mater Misericordiae”, feita para a Santa Casa da Misericórdia de Sesimbra, cerca de 1535-1538, e actualmente no Núcleo Museológico da Capela do Espírito Santo dos Mareantes de Sesimbra, é uma das obras mais importantes do artista, e a sua única pintura sobre esta temática, sendo, como tal, uma das pinturas mais significativas do século XVI em Portugal. A sua recente intervenção de conservação e restauro proporcionou a possibilidade de estudar materialmente a pintura pela primeira vez, através de uma metodologia multianalítica. O estudo incorporou a espectrometria de fluorescência de raios X dispersiva em energia (EDXRF), a microscopia electrónica de varrimento com espectroscopia dispersiva em energia (SEM-EDS), a micro-difracção de raios X (μ-DRX), a micro-espectroscopia Raman (μ-Raman) e a cromatografia líquida de alta eficiência acoplada a detector de foto-diodos (diode array) e detector de massa (HPLC/DAD/MS). O estudo analítico foi complementado pelo exame de Reflectografia de Infravermelhos (IRR), permitindo o estudo da técnica do desenho subjacente, e também pela dendrocronologia de modo a confirmar a data dos painéis de madeira (1535-1538). Os resultados deste estudo foram comparados com outros resultados anteriormente obtidos no estudo da oficina do pintor Gregório Lopes, permitindo encontrar semelhanças e diferenças significativas nos materiais e nas técnicas utilizadas. Este estudo permitiu a análise aprofundada desta pintura e o avanço do conhecimento sobre o seu estado de conservação, trazendo novos dados sobre as técnicas e materiais utilizados por este pintor e contribuindo para o progresso do conhecimento cultural sobre o importante legado artístico da região de Sesimbra., Gregório Lopes (1490-1550) was one of the most prominent painters of the Renaissance and Portuguese Mannerism. The painting “Mater Misericordiae”, made for the Holy House of Mercy of Sesimbra, circa 1535-1538, and currently in the Museological Nucleus of the Chapel of the Holy Spirit of Sesimbra, is one of the artist’s most important works, and his only painting on this theme, being, as such, one of the most significant paintings of the sixteenth century in Portugal. His recent conservation and restoration intervention provided the possibility of materially studying painting for the first time through a multi-analytic methodology. The study incorporated X-ray fluorescence spectrometry (EDXRF), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), micro-X-ray diffraction (μ-XRD), micro-Raman spectroscopy (μ-Raman) and high-performance liquid chromatography coupled to a diode array and mass spectrometry detectors (HPLC/DAD/MS). The analytical study was complemented by the Infrared Reflectography (IRR), allowing the study of the underdrawing technique, as well as dendrochronology to confirm the date of the wood panels (1535-1538). The results of this study were compared with other results previously obtained in the study of the workshop of the painter Gregório Lopes, allowing to find similarities and significant differences in the materials and techniques used. This study allowed the in-depth analysis of this painting and the advancement of knowledge about its state of conservation, bringing novelty on the techniques and materials used by its painter, contributing to the progress of cultural knowledge about the important artistic legacy of the region of Sesimbra.

Within the quest for direct band-gap group IV materials, strain engineering in germanium is one promising route. We present a study of the strain distribution in single, suspended germanium nanowires using nanofocused synchrotron radiation. Evaluating the probed Bragg reflection for different illumination positions along the nanowire length results in corresponding strain components as well as the nanowire's tilting and bending. By using these findings we determined the complete strain state with the help of finite element modelling. The resulting information provides us with the possibility of evaluating the validity of the strain investigations following from Raman scattering experiments which are based on the assumption of purely uniaxial strain.

The study and the characterisation of modern and contemporary oil paintings is still a challenging issue, in particular considering the significant changes in paint production across the 19th and 20th centuries. This paper presents the results of the first physico-chemical integrated study of the artistic materials used in six paintings from the School of Art and Higher Design of Valencia (Escola d'Art i Superior de Disseny, EASD-Valencia), artworks created between 1871 and 1943 by four famous Valencian artists: Salustiano Asenso Arozarena, Salvador Abril I Blasco, Enrique Navas Escuriet and Jose Bellver Delmas. A wide range of inorganic and organic compounds was identified through a multi-analytical approach by means of visible reflectance spectroscopy, XRF, μ-Raman, FTIR and GC–MS. The investigation on the binding media suggests the use of commercial paint formulations including mixtures of drying, slow- and non-drying oils and the presence of Gum Arabic as well. Traditional pigments (such as vermillion, earth pigments, lead white) and modern pigments (such as zinc white, cobalt and chromium-based pigments) were identified together with fillers and extenders. Degradation products, in particular zinc and lead soaps having strong conservation implications, were also detected. This work, focusing on the identification of the palettes and the binding media used by the selected artists, aims at providing meaningful data and interesting case studies that are useful beyond the Valencian painters solely. This study provides new insight into the use of 19th–20th century commercial oil paints and the selection of painters' palette and their artistic production techniques. Besides, this work highlights the necessity of a multi-analytical approach to obtain valuable information for documentation and preventive conservation.

This paper reports the results of an archaeometric characterisation carried out on nineteen samples of Late Roman table and cooking ware by means of the combined use of spectroscopic techniques (colorimetry, FT-IR and μ-Raman). The study attempts at defining the technology adopted in the manufacturing of these ceramics, unearthed during archaeological surveys carried out within the “Ancient Appia Landscapes” project. Successful results were achieved and the reconstruction of the productive process was carried out. Second derivative profiles of IR spectra and μ-Raman analyses allowed defining the mineralogy of ceramic pastes, inferring the local provenance of raw materials and the low attention paid in their manufacturing. If good technological standards were achieved in the production of tableware, cooking ware shows colorimetric and mineralogical evidences of uncontrolled firing conditions, testifying a not-well standardized technological process.

A presente dissertação teve como caso de estudo as salas de exposição permanente de Ourivesaria Portuguesa do Museu Nacional de Arte Antiga. Os principais objetivos deste trabalho foram conhecer as suas condições de exposição atuais, identificando os riscos específicos para a coleção e perceber o processo de deterioração das peças de prataria, uma vez que é o material mais abundante da exposição. Toda esta informação tem como objetivo final fornecer ao museu novas orientações para a seleção de materiais na futura remodelação destas salas, que está prevista para daqui a um ano. Para a concretização deste estudo foi necessário conhecer as caraterísticas do museu, das salas de exposição e expositores, da coleção exposta e também as características ambientais das salas (p.e. temperatura, humidade relativa, iluminação, qualidade do ar). Com a finalidade de se perceber melhor as condições a que estão expostas as peças, foram colocados cupões de prata esterlina nos expositores para caracterização dos produtos de oxidação, que se formassem. As análises realizadas à qualidade do ar, dentro das salas e expositores, permitiram determinar a concentração de poluentes (p.e. compostos orgânicos voláteis e em especifico o formaldeído, ozono e de matérias particuladas). Esta determinação é essencial, para saber que influência estes poluentes podem ter na deterioração das peças. A aquisição destes conhecimentos foi essencial para a realização da avaliação de risco da coleção, através da utilização de um modelo de avaliação de risco – “Cultural Property Risk Analysis Model”. Foram por fim realizadas propostas de mitigação para riscos com maior magnitude de risco para a coleção. Conclui-se que, ao fim de cinco meses de exposição dos cupões de prata esterlina, existem alterações que se conseguiram detetar por μ-Raman, como oxigénio adsorvido na superfície, a formação inicial de óxidos e hidróxidos de prata, e eventualmente óxidos de cobre. No entanto, apenas se podem fazer possíveis atribuições, uma vez que os estudos desta liga são escassos. A avaliação de risco mostrou que os agentes mais preocupantes para a coleção são a presença de poluentes e a humidade relativa incorreta.

Portuguese Science Foundation (FCT) (SFRH/BD/74574/2010; SFRH/BD/70093/2010) FEDER funds through the COMPETE Programme (POCI-01-0145-FEDER-007265; POCI-01-0145-FEDER-007688) PTDC/EAT-EAT/113612/2009 UID/QUI/50006/2013 UID/CTM/50025/2013 This work focuses on the study of the 19th century yellow chromate pigments based on barium - (BaCrO4), zinc -(4ZnCrO(4)center dot K2O center dot 3H(2)O) and strontium (SrCrO4). These pigments, which are reported to shift in hue and darken, have been found in 19th century artworks. A better understanding of their historic manufacture will contribute to the visual/chemical interpretation of change in these colours. Research was carried out on the Winsor & Newton (W&N) 19th century archive database providing a unique insight into their manufacturing processes. One hundred and three production records were found, 69% for barium, 25% for zinc and 6% for strontium chromates, mainly under the names Lemon, Citron and Strontian Yellow, respectively. Analysis of the records shows that each pigment is characterised by only one synthetic pathway. The low number of records found for the production of strontium chromate suggests W&N was not selling this pigment formulation on a large scale. Furthermore, contrary to what the authors have discovered for W&N chrome yellow pigments, extenders were not added to these pigment formulations, most probably due to their lower tinting strength (TS). The latter was calculated in comparison to pure chrome yellow (PbCrO4, 100% TS) resulting in 92% for barium, 65% for zinc potassium and 78% for strontium chromate pigments. This indicates that W&N was probably using extenders primarily to adjust pigment properties and not necessarily as a means to reduce their costs. Pigment reconstructions following the main methods of synthesis were characterised by complementary analytical techniques: Fibre optic reflectance spectroscopy, X-ray diffraction, micro-Raman and micro-Fourier transform infrared spectroscopies. These pigments can be clearly distinguished on the basis of their infrared CrO42- asymmetric stretching fingerprint profile (between 1000 and 700 cm(-1)) and of their Raman CrO42- stretching bands (850-950 cm(-1)). This enabled their identification in historic paint samples: a tube of late 19th century W&N Lemon Yellow oil paint and micro-samples from paintings by three Portuguese painters, Antonio Silva Porto (1850-1893), Joao Marques de Oliveira (1853-1927) and Amadeo de Souza-Cardoso (1887-1918). The good correlation found between the reconstructions and historic samples validates their use as reference materials for future photochemical studies. publishersversion published

This paper presents the results of our investigations on a playing card preserved at The Mūzih-i Āynih va Rushanāī in Yazd, Iran. Conducting micro X-ray fluorescence spectrometry (μ-XRF), micro-Raman spectroscopy (μ-Raman), infrared reflectography (IRR), ultraviolet fluorescence photography, radiography, and optical microscopy, various paints applied on the playing card were identified. According to our analytical studies, red, green, blue, black, and gold-like metallic paints were identified to be a red monoazo pigment (β-naphthol PR 53:1), chrome green, artificial ultramarine blue, carbon black, and brass powder (Dutch metal powder), respectively, dating the playing card to 1895 onward based on the manufacturing date of the red monoazo pigment. Barite was also shown to be mixed with the pigments as an extender. On the other hand, the portrait’s face of the playing card was peculiarly blackened. Our analytical approach toward characterizing the blackened face showed that the black paint was achieved by carbon black and, in other words, the face was not blackened due to the darkening of Pb-bearing pigments. Moreover, it was shown that there was no underdrawing under the black face and the black paint was most probably executed in the same time with the other paints. Considering the possible use of the playing card, it was suggested not to remove the blackened face in the cleaning process since the black paint was a part of the integrity of the playing card.

Within the quest for direct band-gap group IV materials, strain engineering in germanium is one promising route. We present a study of the strain distribution in single, suspended germanium nanowires using nanofocused synchrotron radiation. Evaluating the probed Bragg reflection for different illumination positions along the nanowire length results in corresponding strain components as well as the nanowire's tilting and bending. By using these findings we determined the complete strain state with the help of finite element modelling. The resulting information provides us with the possibility of evaluating the validity of the strain investigations following from Raman scattering experiments which are based on the assumption of purely uniaxial strain.

SiGe islands have been proposed for applications in the fields of microelectronics, optoelectronics and thermoelectrics. Although most of the works in literature are based on MBE, one of the possible advantages of low-energy plasma-enhanced chemical vapor deposition (LEPECVD) is a wider range of deposition rates, which in turn results in the possibility of growing islands with a high Ge concentration. We will show that LEPECVD can be effectively used for the controlled growth of ordered arrays of SiGe islands. In order to control the nucleation of the islands, patterned Si (001) substrates were obtained by e-beam lithography (EBL) and dry etching. We realized periodic circular pits with diameters ranging from 80 to 300 nm and depths from 65 to 75 nm. Subsequently, thin films (0.8–3.2 nm) of pure Ge were deposited by LEPECVD, resulting in regular and uniform arrays of Ge-rich islands. LEPECVD allowed the use of a wide range of growth rates (0.01–0.1 nm s−1) and substrates temperatures (600–750°C), so that the Ge content of the islands could be varied. Island morphology was characterized by AFM, while μ-Raman was used to analyze the Ge content inside the islands and the composition differences between islands on patterned and unpatterned areas of the substrate.

International audience; We report an optical study of 3C-SiC layers grown on 6H-SiC substrates by VLS mechanism using a Si-Ge melt. The photoluminescence and μ-Raman results show a clear and significant incorporation of germanium in the layers from the melt. A photoluminescence emission attributed to Ge related transitions is observed in the infrared region. μ-Raman spectra exhibit two peaks related to the Ge-Ge and Si-Ge bonds. From the characteristics of these Raman peaks, it was found that the amount of Ge incorporated inside the 3C layers increases with increasing Ge content of the melt. This has been verified by Particle-Induced X-rays Emission (PIXE) measurements which gave a Ge concentration varying from ~ 1x1019 to ~ 1x1020 at.cm-3. All these results suggest that Ge incorporates in the VLS grown 3C layers by forming Si-Ge-(C) nanoclusters.

Nel lavoro vengono evidenziati i componenti inquinanti tipici delle massicciate ferroviarie, quali in particolare amianto, metalli pesanti e idrocarburi e le problematiche legate alla loro rilevazione e quantificazione. In particolare vengono evidenziati gli avanzamenti nella tecnica analitica dell'amianto a seguito dell'utilizzo della tecnologia µ-RAMAN. Nel lavoro vengono anche esposti gli aspetti essenziali del lavoro di bonifica delle massicciate e le problematiche legate alla rimozione in sicurezza di ballast contaminati da amianto.

The Lebanese Atomic Energy Commission (LAEC) is incorporated in a development program of the analytical techniques in order to complete the Ion Beam Analysis (IBA). It was decided to get a mass spectrometer coupled to 2D and recently to 3D imaging, by acquiring an ION TOFVTM system equipped with two ionic columns delivering bismuth and argon cluster beams.In this context, my thesis is focused on the optimization of the instrument, recently purchased, for the analysis of samples containing organic compounds. The first subjects of research are the development of a protocol for quantitative analysis of drugs using the « cluster-SIMS-imaging » technique and the Paris meteorite analysis to determine its composition and to localize the organic matter. In the last case a multi-techniques approach was used : IBA in LAEC, µ-Raman et µ-IR around the Soleil synchrotron equipments and µPIXE carried with the AGLAE accelerator (Centre de recherche et de restauration des musées de France, C2RMF).The drug analysis was initiated in Lebanon in collaboration with a local pharmaceutical manufacturer (Mediphar Laboratories) in order to establish new processes for quality control of the final products. My study showed the complexity of the drug quantification which is due to the presence of several active ingredients (AI) and inactive organic and minerals components (excipients) mixed in secret conditions. Matrix effects are dominant and modify the ionic emission leading to significant systematic errors. This complexity has been analyzed with the study of FludiniumTM with two active ingredients. The results of this study allowed to obtain the first calibration curves of the ratio between the two AIs and to quantify them in the commercial drug. The protocol to perform the calibration curve and the « quality» controls were determined. These incorporate a profile analysis to control the homogeneity of the samples and the obtaining standards produced by the pharmaceutical manufacturer following the same process used for the commercial drug. Indeed, the experiments have shown that the preparation of the drug in the laboratory from its elements (AIs and excipients) doesn’t give the same ionic emission as for the commercial drug.The Paris meteorite analysis was initiated by a collaboration with the Institut d’Astrophysique Spatiale d’Orsay team involved in the exobiology and the research of the first prebiotic molecules in the extraterrestrial samples. The work objective is to characterize the organic matter representing few percents in mass in a complex mineral matrix, without any chemical extraction that can induce a modification of these molecules. This study has demonstrated the interest of the multi-techniques approach centered on the mass spectrometry coupled to the ionic imaging for the determination of the main mineral and organic elements of the matrix. µPIXE analysis coupled to the micrometric mapping permits to attribute the distribution of molecular ions and clusters of the mass spectra with different mineral compounds. These attributions continue with the creation of the data base of standard spectra. The organic component was determined and the first hypotheses were considered concerning PAHs (Polycyclic Aromatic Hydrocarbon), IOM (Insoluble Organic Matter) and analogues of amorphous carbon produced par UV irradiation of ices with a gas composition representing different hypotheses for the interstellar clouds. The establish protocols for multi-techniques (incorporating a follow of the sample by mass spectrometry and ion imaging) permits to start the analysis of other extra terrestrial samples collected on earth or in space.; Le Lebanese Atomic Energy Commission (LAEC) poursuit un programme de développement des techniques analytiques pour compléter l’analyse par faisceau d’ions (IBA). Il a décidé de s’équiper d’un spectromètre de masse couplée à l’imagerie 2D puis récemment 3D avec l’acquisition d’un spectromètre de masse IONTOF V™ équipé de deux colonnes ioniques délivrant des faisceaux d’agrégats de bismuth et d’argon. Dans ce cadre, mon sujet de thèse a porté sur l'optimisation de l’instrument nouvellement acquis pour l’analyse d’échantillons contenant des composés organiques. Les premiers sujets de recherche sont la mise au point du protocole d’analyse quantitative de médicaments en utilisant la technique « cluster-SIMS-imaging » et l’analyse de la météorite Paris pour localiser la matière organique et déterminer sa composition. Dans les deux cas une approche multi-technique a été utilisée : IBA au LAEC, µ-Raman et µ-IR autour des équipements de Soleil et µPIXE réalisée auprès de l’accélérateur AGLAE (Centre de recherche et de restauration des musées de France, C2RMF).L’analyse de médicaments a été initiée au Liban en collaboration avec un fabricant local de produits pharmaceutiques (Mediphar Laboratories) dans le but d’établir de nouveaux procédés de contrôle qualité de produits finis. Mon étude a montré la complexité du dosage de médicament due à la présence de plusieurs molécules actives (Principe Actif, PA) et de substances organiques et minérales inactives (excipients) mélangées dans des conditions secrètes. Les effets de matrice sont dominants et modifient l’émission ionique conduisant à des erreurs systématiques importantes. Cette complexité a été analysée avec l’étude du Fludinium™ possédant deux PAs. Les résultats de cette étude ont permis d’obtenir la première courbe d’étalonnage du rapport des deux PAs et de quantifier ceux-ci dans les conditions du médicament commercial. Le protocole pour effectuer cette courbe d’étalonnage et les contrôles « qualité » ont été déterminés. Ceux-ci incorporeront une analyse en profil pour contrôler l’homogénéité des échantillons et l’obtention d’étalons produits par le fabricant en suivant ses processus de fabrication. En effet, les expériences ont montré que la réalisation du médicament en laboratoire à partir de ses éléments (PAs et excipients) ne donnait pas la même réponse ionique que le médicament commercial. L’analyse de la météorite Paris a été initiée par une collaboration avec une équipe de l’Institut d’Astrophysique Spatial d’Orsay impliquée dans l’exobiologie et la recherche des premières molécules pré-biotiques dans des échantillons extraterrestres. Le but des recherches est de caractériser la matière organique représentant quelques pourcents en poids dans une matrice minérale complexe, sans utiliser des méthodes chimiques pouvant induire une modification de ces molécules. Cette étude a démontré l’intérêt de l’approche multi-technique centrée autour de la spectrométrie de masse couplée à l’imagerie ionique pour déterminer les éléments principaux de la matrice minérale et organique. L’analyse par µPIXE avec une cartographie micrométrique a permis d’attribuer les distributions d’ions moléculaires et agrégats des spectres de masse aux différents composés minéraux. Ces attributions se poursuivent avec la constitution d’une base de données de spectres de référence. La composante organique a été extraite et les premières hypothèses de composition ont été envisagées autour des HAPs (Hydrocarbure Aromatique Polycyclique), MOI (Matière Organique Insoluble) et analogues de carbone amorphe produits par irradiation UV de glaces dont les compositions en gaz représentent différentes hypothèses pour les nuages interstellaires. Les protocoles d’analyses multi-techniques établis (incorporant un suivi de l’échantillon par spectrométrie de masse et imagerie ionique) permettent le démarrage d’analyse d’autres échantillons extra-terrestres collectés sur terre ou dans l’espace.

In the frame of an ongoing archeological study on the Sabina area, a countryside close to Rome, white and red samples of roman wall paintings have been investigated by combining X-ray diffraction and different spectroscopic methodologies, namely laser induced breakdown spectroscopy, μ-Raman and Fourier transform infrared attenuated total reflectance spectroscopy. The used multi-technique approach has allowed the unambiguous identification of the red pigment as red ochre and has provided insight on the provenance of both the pigment and the material used for the realization of the wall paintings. The experimental results have confirmed some assumptions on the use of local materials in roman rural architecture. © 2013 Elsevier B.V. All rights reserved.

L'étude des matières picturales des sites d'art rupestre permet grâce aux développements de nouveaux outils et protocoles analytiques de renseigner de manière de plus en plus pointue sur l'origine des pigments, les modes de préparation, leurs interactions avec le support et la conservation des représentations. De tel développement rencontre, néanmoins, à ce jour un réel écueil : la difficulté d'accès aux pigments des grottes ornées paléolithiques assujetties à des contraintes, justifiées, d'ordre conservatoire et patrimoniale. Les travaux menés actuellement soulignent l'importance de développer les méthodes d'analyse pour mieux appréhender les interactions entre les pigments et les supports rocheux notamment dans l'évaluation de la vulnérabilité et de la conservation des panneaux ornés. Une réelle attention existe également sur les informations contenues dans les matières picturales pour travailler de manière plus globale sur l'art rupestre. Un exemple de cette approche est le projet du "Jawoyn RockArt and Heritage Program", des membres de la Jawoyn Association impliquant également les partenaires français (EDYTEM et CNP). Cette étude concerne le panneau de Genyornis, en Terre d'Arnhem (Australie) qui représente d'un oiseau disparu il y a environ 45 000 ans, Genyornis newtoni. Afin de déterminer, i) la nature des constituants des pigments utilisés et leur mode de préparation, ii) leur origine géographique et, iii) la chronologie des peintures, neuf échantillons de peinture ont été prélevés sur le panneau. Des observations macroscopiques (OM), ainsi que des analyses sur la composition des pigments faites par microscopie électronique à balayage couplée à un détecteur de rayons X en énergie dispersive (MEB-EDS) et par microspectrométrie Raman ont été effectuées sur échantillons bruts ou blocs polis. Des oxydes de fer, sous forme d'hématite et de goethite, ont été identifiés au niveau de la couche picturale. Le support matriciel, riche en silicium, a été identifié comme étant une couche d'altération de la roche, dont l'origine reste à ce jour mal connue. La présence d'encroutements de natures différentes a également été mise en évidence. Enfin, la présence inattendue de phosphore reste encore problématique et peut être en lien avec la pratique des " bushfires " australiens. À travers cette première étude sur les pigments de l'art rupestre Jawoyn, nous avons pu souligner l'homogénéité des matériaux utilisés pour la réalisation des peintures du panneau Genyornis, malgré plusieurs spécificités apparentes.

This work aims to characterise the chemical composition of Roman opaque red glass sectilia dated to the 2nd century A.D and to shed light on Roman glassmaking production of different shades of red, from red to reddish-brown. Due to the lack of technical historical sources for this period many questions about technological aspects still remain. In this project a multi-disciplinary approach is in progress to investigate the red glass sectilia with several red hues from the Imperial Villa of Lucius Verus (161&ndash, 169 A.D.) in Rome. First, colorimetric measurements were taken to identify the various red hues. The second step was chemical characterization of the samples and the identification of crystalline colouring phases. Particle Induced X-Ray Emission (PIXE) analysis was used to investigate the chemical composition of these glass samples, while the crystalline phases were identified by Raman Spectroscopy and Scanning Electrons Microscope with Energy Dispersive X-ray Spectrometry (SEM-EDS). Using SEM-EDS nanoparticles were detected as a colouring agent, the chemical composition and the morphology of which has been studied in depth. This information has been compared with the colorimetric analysis to establish any correlation with the different colour hues.