Emilie Chalmin
Savoie University, EDYTEM, Faculty Member
Research Interests: Humanities and Art
PosterInternational audienc
Research Interests: Materials Engineering, Mineralogy, Condensed Matter Physics, Chemistry, Biomineralization, and 13 moreMedicine, France, Cave, Fossils, Carbonate, Bacteria, Vaterite, Calcite, Prehistoric Cave, Calcium Carbonate, Electron Probe Microanalysis, Biochemistry and cell biology, and Conservation of Rock Art
Whether as engravings, drawings, paintings, stencils, or prints, rock art was made on rock surfaces devoid of protective coating. From the moment of its manufacture, it has therefore been subject to a range of environmental conditions and... more
Whether as engravings, drawings, paintings, stencils, or prints, rock art was made on rock surfaces devoid of protective coating. From the moment of its manufacture, it has therefore been subject to a range of environmental conditions and susceptible to a range of environmental impacts, each of which could have changed through time. In this chapter, the authors discuss the biotic, mechanical, and chemical processes that can affect rock art at its interface with the rock matrix and the atmosphere, together known as taphonomy. Given the complex interplay of age, environment, and processes, understanding alteration mechanisms affecting rock art sites and adequately assessing ways of mitigating deterioration require site-specific investigations and complementary scientific fields
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The colors of archaeomaterials provide important insights into ancient human activities, technologies, capabilities, symbols, and craftsmanship, making the study of color an important aspect of archaeological, art historical, and... more
The colors of archaeomaterials provide important insights into ancient human activities, technologies, capabilities, symbols, and craftsmanship, making the study of color an important aspect of archaeological, art historical, and historical research. The color origins of archaeomaterials are usually related to major but also minor or trace elements, or minor components, in a particular chemical environment. However, the color can be changed over time due to alteration phenomena. Hence, the analysis of these archaeomaterials requires very sensitive and noninvasive methods. In addition to the direct measurement of color, other physicochemical methods, such as X-ray absorption spectroscopy, are well suited to study the colors in these archaeomaterials. Here, the authors present an overview of the methods most commonly used to study these materials. The pigments, paints, and minerals that are of particular importance in the study of cultural heritage are summarized and present a historical overview of the archaeometric study of such materials presented. In conclusion, several case studies are presented illustrating the potential of such studies to further inform our understanding of ancient human societies.
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The most common studies on colouring matter concern the question of the “chaîne opératoire” from procurement to use, dealing distinctively with archaeological remains and rock art. Only a few studies have been done on the link between... more
The most common studies on colouring matter concern the question of the “chaîne opératoire” from procurement to use, dealing distinctively with archaeological remains and rock art. Only a few studies have been done on the link between excavated pieces and rock art, and even less have taken into account the correlation with geological origin. The “Grotte aux Points” presents the particularity of being decorated and archeological excavations reveal many pieces of coloured and colouring remains which are iron oxide-rich rocks brought to the site by Palaeolithic people. The red Palaeolithic paintings present a few palm-points, great signs and figurative drawings: a horse, a bison and ibexes.In 2015, coherent colouring matters, coloured limestone fragments and one µ-sample of painting were studied with complementary physico-chemical methods. To describe their morphology and composition, different instruments were used on macroscopic and microscopic scales: optical microscope, scanning electron microscope (SEM), and transmission electron microscope (TEM), both coupled with dispersive X-ray energy probe (EDX). 10 objects were studied using proton induced X-ray emission (PIXE) in order to obtain quantitative chemical data on major and trace elements. Except for the TEM which gives information concerning the iron oxide crystal morphology and potential heat-treatment, non-invasive and non-destructive methods have been privileged to preserve the archaeological artefacts.About forty pieces of solid colouring agents were excavated in the Palaeolithic occupational levels. Most of the pieces have millimetric size (< 5 mm). At least three different raw ferruginous materials were discriminated including a ferruginous clayey rock containing green minerals dispersed in the matrix. We think that this mineral phase, which still needs to be clearly identified, is a good indicator of the geological origin of this kind of rock.In addition, three centimetric fragments of wall painting (from 3 cm to 20 cm) were discovered at the foot of the “large signs” panel. Finally, in 2012, a red palm-point with black charcoal pigment superposition was sampled from the “Niche aux Points”.The twenty-five archaeological remains (coloured limestone fragments and solid colouring agents), the 3 painted wall fragments and the micro-sample of painting were analysed in order to approach the chronology of the colouring matter used.These observations combined with chemical measurements actually permit (i) to characterize the signal of the environment on the different objects, (ii) to identify differences between macro-observations and geochemical fingerprints on the coherent matters (figures 10, 11). The raw material properties privileged by Palaeolithic people during supply were identified. First results are encouraging and enable to improve the methodology, particularly on a chemical point of view.Les fouilles conduites sous le porche de la Grotte aux Points ont mis au jour des matières colorantes solides et des résidus colorés sur des clastes calcaires au sein des dépôts archéologiques Paléolithique supérieur. De plus, dans la partie profonde de la cavité, des écailles de paroi présentant des aplats rouges ont été découvertes au pied de parois ornées. Cette association offre l'occasion de questionner les relations entre ces vestiges sous l'angle des choix de matières premières et des modalités de transformation, informations qui participent à la définition du cadre chronologique de fréquentation de la grotte, tant au niveau de son entrée que de la galerie ornée. Nous avons ainsi déterminé, en les comparant, les particularités pétrographiques, minéralogiques et géochimiques de ces matières. L'approche multi-scalaire adoptée repose sur la complémentarité des méthodes d'investigation ce qui permet de distinguer plusieurs géomatières colorantes au sein du corpus. En particulier, certains dépôts sur les clastes peuvent être attribués à des causes taphonomiques, alors qu'une forte parenté a pu être établie entre une géomatière colorante solide et les aplats rouges sur écaille de paroi
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Whether as engravings, drawings, paintings, stencils, or prints, rock art was made on rock surfaces devoid of protective coating. From the moment of its manufacture, it has therefore been subject to a range of environmental conditions and... more
Whether as engravings, drawings, paintings, stencils, or prints, rock art was made on rock surfaces devoid of protective coating. From the moment of its manufacture, it has therefore been subject to a range of environmental conditions and susceptible to a range of environmental impacts, each of which could have changed through time. In this chapter, the authors discuss the biotic, mechanical, and chemical processes that can affect rock art at its interface with the rock matrix and the atmosphere, together known as taphonomy. Given the complex interplay of age, environment, and processes, understanding alteration mechanisms affecting rock art sites and adequately assessing ways of mitigating deterioration require site-specific investigations and complementary scientific fields.
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The Large cave of Arcy-sur-Cure is well known as well as for its prehistoric paintings and for its limestone concretions. Unfortunately, formation of calcite layers has totally or partially obstructed paintings. The phenomenon of calcium... more
The Large cave of Arcy-sur-Cure is well known as well as for its prehistoric paintings and for its limestone concretions. Unfortunately, formation of calcite layers has totally or partially obstructed paintings. The phenomenon of calcium carbonate (CaCO3) growth in karstic environment is very common and could be occurred in pure abiotic conditions or combined with microbiological influence. In the frame of the still on-going restoration project, this study focuses on the role of microorganisms in the formation of the calcite layer. From extracted bacteria from natural calcite samples taken in the cave, we tested their ability to start calcite growth. These synthetic samples have been investigated by means of synchrotron-based methods and more particularly by X-ray diffraction and then compared with natural samples from the cave. The biotic samples reveal the presence of crystalline carbonate phases and amorphous calcium phosphate phase. Interpretation of these data enables us to draw up conservation measurements and further express recommendations for the future.
Research Interests: Geology, Mineralogy, Cave, Carbonate, Karst, and 4 moreCalcite, Calcium Carbonate, IFRAO, and Biogenic
ABSTRACT
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Palaeolithic rock art belongs to the most ancient artisitc representations of human beings. Conserved under very exceptional conditions, it is today threatened by numerous alteration phenomena, among them the formation and interaction... more
Palaeolithic rock art belongs to the most ancient artisitc representations of human beings. Conserved under very exceptional conditions, it is today threatened by numerous alteration phenomena, among them the formation and interaction with calium carbonate concretions. The cave “Grande Grotte” of Arcy-sur-Cure (Yonne, France) with prehistoric paintings shows important calcite concretions. Two types of calcite have been observed on the walls: translucent yellowish layers and opaque white or grey layers that obscure the paintings. Other calcite types are present in the lakes of the cave (floating calcite rafts at the surface of the lake and soft calcite at the bottom of the lake). The morphology of the different calcites was observed at different scales by optical microscopy with normal and polarized light, SEM and TEM. The elemental composition was measured by micro-PIXE and the structure by XRD, IR and Raman spectroscopy. The bacterial diversity and its role in calcite formation were assessed by culture and 16S-SSCP in order to distinguish and to assess various abiotic and biotic formation mechanisms. The investigation of calcite characteristics enables conclusions on the formation mechanism and on a biotic or abiotic origin of the calcites. The change of calcite types on the walls reveals changes of the environmental cave parameters. In addition, interactions of calcites with the prehistoric paint layer could be evaluated.
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Abstract The soil-derived organic matter incorporated in speleothems provides a proxy for the impacts of climate and environmental changes on the surrounding catchment. These organic proxies, combined with inorganic proxies, can be used... more
Abstract The soil-derived organic matter incorporated in speleothems provides a proxy for the impacts of climate and environmental changes on the surrounding catchment. These organic proxies, combined with inorganic proxies, can be used to investigate variations in carbon fluxes. The present article describes a method for obtaining high spatial-resolution estimations of speleothem organic carbon concentrations by using the relationship between liquid phase fluorescence and the organic carbon contents of soil samples. Applying this method to soil and stalagmite samples from three locations in the French Prealps gave estimated stalagmite carbon concentrations of between 0.27 and 3.03 mg C/g of calcite, which are consistent with measured concentrations reported in the literature. We assessed the high-resolution reliability of our procedure by comparing TOC estimations with solid phase fluorescence values for samples taken every 2-mm along one of the stalagmites (TAM). Due to variations in the optical properties (e.g., optical density) of the calcite, revealed by Near Infra Red Reflectance, it was necessary to draw up a nonlinear model in order to obtain good estimates (R 2 = 0.81) of organic carbon concentrations from solid-phase fluorescence results. The resulting high-resolution map of organic carbon concentrations along the TAM sample was consistent with the recent history of the area's environment. Our results show that variations in carbon flux in mountain karst environments are strongly linked to changes affecting the area's soils.
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Phosphorus (P) plays an important role for the development of lake ecosystems. In particular, lake productivity is strongly linked to the nutrient bioavailability, which depends on P species. The natural dynamic of this nutrient is... more
Phosphorus (P) plays an important role for the development of lake ecosystems. In particular, lake productivity is strongly linked to the nutrient bioavailability, which depends on P species. The natural dynamic of this nutrient is largely controlled by soil cover evolution. ...
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Les stalagmites constituent des enregistreurs particulierement pertinent des flux de Matieres Organiques (MO) dans l'environnement. Extraites des sols lors de la percolation des eaux meteoriques, ces MOs sont piegees dans les matrices... more
Les stalagmites constituent des enregistreurs particulierement pertinent des flux de Matieres Organiques (MO) dans l'environnement. Extraites des sols lors de la percolation des eaux meteoriques, ces MOs sont piegees dans les matrices cristallines des stalagmites lors de leur croissance. Differentes methodes d'imagerie geochimique permettent de quantifier voire de qualifier cette MO au sein de ces archives naturelles. Mais pour utiliser pleinement le potentiel de cet enregistrement, il convient de determiner les conditions de partitionnement de cette matiere a differents stades de son transfert (interactions sol/eau, eau/solide puis eau/ calcite). Cette presentation est centree sur les modalites d'incorporation des MO lors de la cristallisation de calcites synthetiques et sur l'utilisation de ces standards pour interpreter des donnees issues d'imagerie en μ- FTIR de calcites naturelles. Differents mecanismes peuvent etre a l'origine du piegeage de MO au sein de la calcite naturelle qui forme les stalagmites. Pour etablir un cadre general decrivant cette interaction calcite/MO, des echantillons de calcite ont ete synthetises en variant les concentrations en acides humiques (Aldrich) dans la solution de cristallisation. Des methodes micro-analytiques qualitatives et semiquantitatives complementaires ont ete appliquees afin de decrire ces echantillons de calcite synthetique d'un point de vue morphologique et structural a differentes echelles. Les methodes de microscopie optique, de MEB, de spectroscopie FTIR, de diffraction X (XRD), et de spectroscopie XANES (x-ray absorption near edge structure) confirment que l'addition de MO a un effet direct sur la cristallisation de la calcite (taille des cristaux, forme cristalline). Les methodes semiquantitatives (spectroscopie UV-vis, spectrophotometrie et spectrofluorescence) mettent en evidence un fractionnement lors de la croissance et une evolution moleculaire des MO durant l'inclusion dans la matrice cristalline. Enfin, la cartographie en fluorescence X et le XANES (par source synchrotron) ont permis d'analyser localement, sur les calcites naturelles et synthetiques, la relation calcite/MO. Ces differents analyses montrent le potentiel des sulfures comme element traceur des matieres organiques piegees dans la calcite. Cette utilisation possible du sulfure, issue des analyses realisees sur les echantillons synthetiques, est appliquee a une stalagmite prelevee dans une carriere de calcaire situee proche de Grenoble qui couvre la derniere cinquantaine d'annees.
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ABSTRACT La recherche de la matière organique (MO) dans les stalagmites en tant que traceur environnemental s&#39;inscrit dans une problématique visant à décrire la dynamique actuelle et l&#39;évolution passée de... more
ABSTRACT La recherche de la matière organique (MO) dans les stalagmites en tant que traceur environnemental s&#39;inscrit dans une problématique visant à décrire la dynamique actuelle et l&#39;évolution passée de l&#39;environnement. Les matières organiques (MO) piégées dans les spéléothèmes sont directement issues de l&#39;environnement (végétation, sols). Leur suivi au sein des géomatériaux est aisé en raison de leur propriété spectroscopique, la fluorescence. Cette méthode est peu discriminante vis-à-vis de la différenciation des nombreuses variétés de MO naturelles. L&#39;approche analytique passe, quant à elle, par une molécule traceur permettant de remonter au précurseur de la MO, sans pour autant tenir compte de la matrice ni des transferts. Appuyée sur la complémentarité de ces approches, l&#39;investigation plus spécifiquement des matières humiques dans la calcite vise à connaître les conditions de partitionnement de cette matière à différents stades de son transfert (interactions sol/eau, eau/solide puis eau/ calcite). Différents mécanismes de piégeage de la MO dans la matrice de calcite peuvent être impliqués au cours de la croissance cristalline de la calcite et en fonction du type de MO. Plusieurs facteurs spécifiques liés aux échantillons naturels (défauts cristallins, variation chimique, changement de densité ...) sont limitant pour permettre de différencier ces différents mécanismes par une approche globale. Pour s&#39;affranchir de ces limites, une méthodologie basée sur la caractérisation d&#39;échantillons analogues synthétiques est proposée. Des échantillons de calcite sont synthétisés dans différentes conditions pour y introduire des acides humiques standards et naturels. Afin d&#39;identifier le type d&#39;interaction entre la matrice et l&#39;acide humique, les échantillons sont analysés à différentes échelles d&#39;un point de vue morphologique et structural (microscope optique, microscope électronique à balayage (MEB), microscopie FTIR à source synchrotron, diffraction des rayons X (DRX), spectroscopie d&#39;absorption X (XANES)). D&#39;autres méthodes semi-quantitatives (UV-vis, colorimétrie, spectroscopie de fluorescence) permettent une approche qualitative et renseignent sur le fractionnement et l&#39;évolution moléculaire des MO lors de l&#39;inclusion dans la matrice. La combinaison de ces techniques et la comparaison avec des échantillons naturels a permis d&#39;identifier différents modes d&#39;insertion par rigidification de la structure de la MO, comme par exemple la formation de colloïdes ou par adsorption avec formation de liaisons hydrogène à la surface de la calcite. Aucune modification structurale n&#39;a été observée dans la matrice de calcite. L&#39;insertion de MO ne semble pas perturber la cristallisation ni induire de défauts structuraux significatifs.
Research Interests: Chemistry and Humanities
Organic matter (OM) entrapped in calcite is regularly used for environmental studies; however, insertion mechanisms and types of interaction remain poorly understood. The present study used a new methodology to investigate interactions... more
Organic matter (OM) entrapped in calcite is regularly used for environmental studies; however, insertion mechanisms and types of interaction remain poorly understood. The present study used a new methodology to investigate interactions between OM and the calcite matrix during crystallization processes with humic acid (HA) entrapment. A multimethod approach confirmed that HA is both adsorbed onto the calcite surface and incorporated into the calcite lattice during crystallization. Our results also confirm the log-linear correlation between fluorescence intensity and calcite matrix HA concentration. Fourier transform infrared spectroscopy showed that HA in colloidal conformation is adsorbed onto the calcite surface as a result of the structure of the OH stretching band. We also developed a new method based on synchrotron analysis that uses sulfur as a tracer element for entrapped HA and that localizes the OM electrostatically adsorbed onto the calcite surface. Changes in the sulfur environment, determined using X-ray absorption near-edge structure spectroscopy, indicated more complex insertion mechanisms than simple adsorption of HA during calcite crystallization. Desorption experiments revealed the stability of the OM atomic structure and its layered nature. These results allowed us to draw up a general model of OM insertion in calcite.
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We have applied a combination of synchrotron-based techniques (μ-XRD, μ-XRF, and µ-XANES) to determine the mineralogy and the elemental distribution of metals in partially altered sulphide-mineralization fragments deposited within an... more
We have applied a combination of synchrotron-based techniques (μ-XRD, μ-XRF, and µ-XANES) to determine the mineralogy and the elemental distribution of metals in partially altered sulphide-mineralization fragments deposited within an open-air waste-rock dump (Libiola mine, eastern Liguria, Italy). In this dump AMD processes are active and intense and sulphide-mineralized clasts progressively undergo oxidation originating centimetric-thick hardpans cemented by secondary iron oxides and oxyhydroxides. Selected samples, containing the transition from unaltered sulphides to secondary oxidation products have been analyzed along several millimetric transects. The results evidenced that sulphides (pyrite + chalcopyrite sphalerite) oxidation starts from the crystals rims or from intra-grain microfractures. Sulphide-S firstly oxidizes to sulphate and then is rapidly leached out from the system. The altered layers are composed almost exclusively of Fe-oxides (hematite) and -oxyhydroxides (goethite and minor bernalite) that replace sulphides and fill intra- and inter-grain interstices. Elemental maps and μ-XRF transects evidenced that these secondary minerals efficiently and selectively scavenge many of the elements released during sulphides (e.g. Cu, Zn, As) and gangue minerals (e.g. Ni, Cr, Al) alteration.
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Research Interests: Humanities and Art
International audienc
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International audienc
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Research Interests: Humanities and Art
Research Interests: Humanities and Art
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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... more
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
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ABSTRACT This paper presents new results of on-wall and excavated pigments from two major rock art sites in northern Australia: the ‘Genyornis’ site, and Nawarla Gabarnmang. The former site has been argued in the archaeological literature... more
ABSTRACT This paper presents new results of on-wall and excavated pigments from two major rock art sites in northern Australia: the ‘Genyornis’ site, and Nawarla Gabarnmang. The former site has been argued in the archaeological literature to feature a painting of Genyornis newtoni, thought to have become extinct across Australia 40-45,000 years ago. The second site, Nawarla Gabarnmang, has extensive paintings on its ceiling and pillar walls as well as numerous coloured rocks (some of which are demonstrably ochre crayons) recovered by excavation. To determine the constituents and modes of preparation, pigment sources, and the potential antiquity of on-wall paintings at the ‘Genyornis’ site, tiny pieces of both pigmented and unpigmented rock were sampled from the‘Genyornis’ panel. X-ray fluorescence, SEM-EDX, PIXE, Raman and infrared spectroscopies, and XRD analyses were undertaken to determine the natural or cultural status of the excavated coloured rocks (potential ochre pieces)from Nawarla Gabarnmang. This paper presents results obtained so far.
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Being one of the ten alpine sites of schematic rock art painting, the Rocher du Chˆateau(Castle Rock) is a remarkable site situate on a main transalpine route at 1750m.a.s.l. inthe Vall ee de la Maurienne (France). Despite the first... more
Being one of the ten alpine sites of schematic rock art painting, the Rocher du Chˆateau(Castle Rock) is a remarkable site situate on a main transalpine route at 1750m.a.s.l. inthe Vall ee de la Maurienne (France). Despite the first mention of the presence of rock art,few studies have been carried out on this site (Nehl, 1976). Since archaeological surveys andsome archaeological excavations were realized (between 1989 and 2003) attesting a Neolithicoccupation and the discovery of some coloring and colored matter from the Neolithic layersattributed to the phase 2 of the ”Square Mouthed Pottery” Italian culture (4500-4000 BCE).In order to question the chronology of the ”schematic” painting phenomena occurring in theMediterranean area, the integrated study of the Rocher du Chˆateau involved both the rockart description and the comparaison between fragments of coloring materials to the paint-ing matters preserved in the bedrock surface. By combining non-invasive in situ methods(numerical binocular and Raman spectroscopy) and micro-sampling, the understanding ofweathering process before and after painting deposit is proposed and the identification of thepigment is realized. Complementary physico-chemical analyses have been developed at sev-eral scales of observation to identify various compositions of the fragments of coloring matter and of the colored pebble fragments. Thanks to these data, discussion could be proposed tounderstand the potential link between the artefacts, the production of coloring matter. andthe application of painting matter. The presence of an extremely unusual mineral of ironsilico-phosphate raises the question of the origin and of the supply in coloring matter
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The phenomenon of speleothem formations made of calcium carbonate (CaCO3) in limestone environments is well known. These speleothems can have with various sizes and shapes depending on the geochemical growth parameters. In caves with... more
The phenomenon of speleothem formations made of calcium carbonate (CaCO3) in limestone environments is well known. These speleothems can have with various sizes and shapes depending on the geochemical growth parameters. In caves with prehistoric paintings, the formation of subsequent CaCO3 layers can have effects on their preservation and can also partially or totally obstruct them. Thanks to fortunate circumstances, Paleolithic figures were discovered about 20 years ago, hidden behind thick opaque CaCO3 layers, on the walls of the Western gallery of the Large cave of Arcy-sur-Cure. In the frame of an on-going restoration program, a large number of carbonate concretions coming from the Large cave were analyzed in combination with different series of synthetic calcium carbonates. Natural and synthetic samples were studied using complementary microanalytical laboratory techniques. Micro-x-ray diffraction (μXRD), micro-x-ray fluorescence analysis (μXRF) and x-ray absorption near-edge structure spectroscopy (μXANES) based on synchrotron radiation also enabled a more detailed distinction of the different constituents present in these samples at microscopic scale. These investigations allowed gaining information on calcite growth mechanisms, the most important parameters influencing the calcite growth, evaluating the impact of microbial activity, the protective effect of the calcites on prehistoric panels and the proposal of conservation measures.
Research Interests: Geology, Mineralogy, Prehistory, Cave, Carbonate, and 3 moreCalcite, Speleothem, and Calcium Carbonate
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