Philippe Walter

Philippe Walter
Sorbonne Université | UPMC · Laboratoire d'Archéologie Moléculaire et Structurale (LAMS)

About

220
Publications
43,643
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
6,126
Citations

Publications

Publications (220)
Article
Full-text available
If ancient written sources and the visual analysis of polychromies have recently revealed the complexity of the technique of painting on statues and their frequent restoration, the non-invasive punctual chemical analyses carried out do not allow one to access the chemical composition of the different paint layers. This paper presents the analysis o...
Article
Full-text available
British 19th century painters formulated gelled systems often described as ideal paint mediums. These so-called megilps or gumtions are based on common paint materials like linseed oil, lead acetate, and mastic resin, and allowed painters such as J.M.W Turner to improve their paint's properties and achieve unprecedented effects in an age of innovat...
Article
Time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging is a surface analysis technique that identifies and spatially resolves the chemical composition of a sample with a lateral resolution of less than 1 μm. Depth analyses can also be performed over thicknesses of several microns. In the case of a painting cross section, for example, TOF...
Article
Certain objects and know‐how have cultural significance in our societies, that is, they are inherited from a common past and are meant to be preserved and passed down from generation to generation. These can be works of art such as frescoes, paintings or jewelry, but also statues, ruins, and everyday objects such as pottery, tools, remedies, and co...
Article
Egg-tempera painting is a pictorial technique widely used in the Middle Ages, although poorly studied in its physico-chemical aspects until now. Here we show how NMR relaxometry and rheology can be combined to probe egg-tempera paints and shed new light on their structure and behavior. Based on recipes of the 15th century, model formulations with e...
Article
Crack the code of egg-tempera paints: The macroscopic and microscopic properties of egg-tempera paint prepared with green earth are highlighted via rheology and NMR relaxometry. Abstract Egg-tempera painting is a pictorial technique widely used in the Middle Ages, although poorly studied in its physico-chemical aspects until now. Here we show how...
Article
The material evidence for the wax finish on ancient marble statues, known as ganosis, is scarce and controversial, although Greek and Latin sources describe the recipes and cultural value of this treatment. The surface treatment of a colossal Roman head from the Roman theatre of Dougga (Tunisia), dated to the end of the second century CE, is studie...
Article
The identification of « applied brocades » in painted sculptures from the Savoy Duchy, dated from 1480 to 1530, has motivated the development of an analytical process to allow a systematic characterization of those decorations. It combines macro- and micrometer surface observations, non-invasive analyses using portable instrumentation, and nondestr...
Article
The two paintings Infant Bacchanals (Museo Nazionale d'Arte Antica, Palazzo Barberini, Rome, Italy) executed by Nicolas Poussin (Les Andelys, 1594-Rome, 1665) in around 1626 are thought to have been painted "a guazzo", which means either with a glue or with an egg binding medium. To date, this has never been confirmed through analysis. Dual-beam ti...
Article
Two polychrome sculptures from the late Middle Age were investigated by means of non-invasive techniques with the aim of characterizing sophisticated relief decoration named "applied brocade". Here, we have used portable instrumentation solely in order to perform X-ray powder diffraction and fluorescence measurements at the surface of the sculpture...
Article
Full-text available
ThomX is a new generation Compact Compton Source. It is currently commissioned by and at the IJCLab (Laboratoire de physique des 2 infinis - Irène Joliot-Curie (UMR9012)) at Orsay. The first beam is expected at the begining of 2021. The aim of ThomX is to demonstrate the characteristics of an intense and Compact (lab-size) X-ray source based on Com...
Article
Visible and near infrared hyperspectral imaging have allowed unprecedented analyses of two major works of art of the National Museum of Catalan Art (MNAC), 15th century Gothic altarpieces: (1) Madonna of the ‘Consellers’ (Lluís Dalmau, 1443–1445) [1], an impressive piece of Catalan painting, inspired by J. van Eyck and (2) Princess Eudoxia exorcise...
Article
Alizarin (Az) lake is a typical example of madder lake pigments that are widely used in cultural heritages. Previous work focused on the complex formation in solution, theoretical models and crystallized stoichiometric structures (Az /Al3+ = 1:1 or 2:1). However, the classical recipe for preparing madder lake demonstrated that the dosage of dye was...
Article
Full-text available
Pachacamac is the name of the 15th-16th century Inca sanctuary on the Peruvian coast as well as the name of one of the principal oracles of Inca divinities. This effigy would have been destroyed by Pizarro in 1533 during his visit to the great monumental complex, and as such the originality and antiquity of the wooden statue—the so-called Pachacama...
Chapter
Full-text available
Our scientific analysis of two paintings by Poussin—Venus presenting Aeneas with his Arms (painted in 1639), and Eliezer and Rebecca at the well (painted towards the end of his life, in the early 1660s)—is presented here in the context of the philosophical and poetic culture that inspired them. In addition to determining the pigments Poussin employ...
Article
Full-text available
Anthropologists and ethnomusicologists assert that there is no society without song, and more specifically, there is no ritual or celebration without accompanying sound. The production of sounds in social contexts is very ancient. Here, we report on the study of a seashell from the decorated cave of Marsoulas and demonstrate that the Magdalenian oc...
Article
Little is known concerning Phoenician and Punic cosmetics, and pertinent studies and analyses on archaeological finds are particularly scanty. The present study has taken into account 22 archaeological red and pink Punic make-up samples collected in several Sicilian museums. The samples were analyzed by infrared spectroscopy, Raman microscopy, and...
Article
Green earth is a common green pigment based on celadonite and glauconite, used since Antiquity by artists. Two geological minerals, eight commercial green earth pigments and a sample taken from a historical location in Monte Baldo were characterized. A set of different techniques including X-Ray diffraction (XRD), scanning electron microscopy coupl...
Article
The use of ochre in mortuary practices was widespread during prehistory. In northern Thailand, several painted rock-shelters attributed to Iron age or Neolithic cultures have provided burials characterized by the presence of pigment fragments and ochres deposits. In the case of Doi Pha Kan, data collected during excavations have highlighted the imp...
Article
Covering with polyorganosilane (POS) was proved as an effective way to enhance the chemical and thermal stability of clay/dye hybrid pigments. But the photostability and interactions with clay minerals, dyes and POS layer has never been reported. In order to investigate above issues, new organic-inorganic hybrid pigments based on halloysite (Hal) a...
Chapter
Recipes describing the controlled mixture and reaction of fat/oil with lead-based compounds have been known and employed since antiquity until modern times. Two major fields have developed such practices: pharmacy, for the preparation of lead plasters (i.e., dressings made of lead-based compounds and fat/oil) and related unguents, and painting, for...
Article
The fading of organic dyes is a serious challenge for conservation of art works. Inspired by the ancient Maya blue pigment, a hybrid pigment of halloysite (Hal) and alizarin (AZ) was prepared by adsorption in aqueous solution. In addition, a layer of polyorganosilane (POS) is used to cover the surface of the hybrid pigment to enhance the chemical r...
Article
The Kossel effect is the diffraction by a periodically structured medium, of the characteristic X-ray radiation emitted by the atoms of the medium. We show that multilayers designed for X-ray optics applications are convenient periodic systems to use in order to produce the Kossel effect, modulating the intensity emitted by the sample in a narrow a...
Article
This entry focuses on the physicochemical analysis and cultural study of cosmetics and fragrances that were prepared and used in ancient cultures of the Old World and New World. The characterization of these products is the key to obtaining the global recipe to understand the connection between body color, aromatics, magic/religious beliefs, and so...
Article
Full-text available
Lead white, composed of a mixture of cerussite and hydrocerussite (respectively PbCO3 and Pb3(CO3)2(OH)2), is often associated in paintings with other white pigments, especially calcite. By combining in-situ analyses with paint reconstructions, we attempt to get a better understanding of the role of this addition of calcite and to investigate how a...
Article
Full-text available
Hyperspectral imaging allows the acquisition of representative information on cultural heritage objects. For a complete identification of the chemical compounds present, one needs instruments employing different forms of radiation, sensitive to different chemical features. Data treatment workflows are commonly developed for a single spectroscopic t...
Article
We present the observation of the angular distribution of a characteristic x-ray emission through a periodic multilayer. The emission coming from the substrate on which the multilayer is deposited is used for this purpose. It is generated upon proton irradiation through the multilayer and detected with an energy sensitive CCD camera. The observed d...
Article
By combining Kossel diffraction with particle induced X-ray emission, we have developed a new methodology to analyze nano-scale thin films. We report the Kossel diffraction generated by irradiating Pd/Y based nano-scale periodic multilayers with 2 MeV protons. The intensity of characteristic Pd Lα X-ray emission is measured as a function of the det...
Article
The Alcazar Palace (Seville, Spain) is famous for its ceramic decorations; 16th century wall tiles of different typologies have been analyzed in order to relate the manufacturing process of their colored glazes to the evolving technologies of the Renaissance. Chemical and mineralogical compositions have been determined in situ by non‐destructive X‐...
Article
Hybrid materials based on montmorillonite, a cationic polymer and carminic acid were prepared. The surface charge of montmorillonite was inversed thanks to the cationic polymer, polydiallyldimethylammonium chloride. Samples were characterized by a set of different techniques including Infrared (IR) and Nuclear Magnetic Resonance (NMR) spectroscopie...
Article
The pigment use in the Tomb of the Reliefs (fourth century BC) and four other tombs (seventh to fourth century BC) in the Etruscan Banditaccia Necropolis near Cerveteri, Italy, has been investigated. We made use of X‐ray fluorescence (XRF) and Raman spot analysis, XRF imaging, infrared luminescence and photography supported by Dstretch contrast enh...
Article
Hybrid pigments have attracted great interest due to their stability and physicochemical properties that can be used in paintings, artworks and in the field of cultural heritage. The study of new materials includes the search for new pigments by immobilization of the dyes in resistant substrates such clays minerals to get new colour fonts and mater...
Article
Of the once colourful decoration of antique Greek statues only few traces remain today. But these allow one to reconstruct part of the polychromy, based on visual and microscopic inspection and spot analysis with spectroscopic methods. For the first time we used mobile hyperspectral reflectance imaging in the visible and near infrared range and sca...
Article
Full-text available
We present here the combination of in situ non invasive techniques to investigate a precious 15th century illuminated manuscript of Petrarch’s work, De remediis utriusque fortunae held in the Méjanes library in Aix-en-Provence (France). X-Ray fluorescence spectroscopy, mapping and point analysis, and visible reflectance hyperspectral imaging allow...
Article
Map-X is a planetary instrument concept for 2D X-Ray Fluorescence (XRF) spectroscopy. The instrument is placed directly on the surface of an object and held in a fixed position during the measurement. The formation of XRF images on the CCD detector relies on a multichannel optic configured for 1:1 imaging and can be analyzed through the point sprea...
Article
A novel full‐field X‐ray fluorescence spectrometer developed for cultural heritage applications is presented. Named “CartiX,” it was designed for routine deployment in the field (museum, archeological site) and uses a concept under development at NASA for planetary exploration. CartiX utilizes 2 miniature X‐ray tubes, a square pore Micro‐channel Pl...
Article
Full-text available
In this study we present the first physicochemical study of 231 drugs preserved in the main show-case at the ‘Spezieria di Santa Maria della Scala’ (Rome), a conventual pharmacy founded in the late seventeenth century by the Order of the Discalced Carmelites. This pharmacy is therefore associated with the religious order of Spanish origin that at t...
Article
Through the paintings of the old masters, we showcase how materials science today provides us with a vision of the processes involved in the creation of a work of art: the choice of materials, the painter's skill in handling these materials, and the perception of the finished work.
Article
Full-text available
The study of La Famille Soler using non-invasive imaging, molecular, structural, and elemental analysis allowed the re-examination of changes of the work. Considered as the earliest of Picasso’s versions of Le déjeuner sur l’herbe by E. Manet, evidence suggests that an underlying landscape painted by Vidal in 1903 also referred to Manet’s masterpie...
Article
Full-text available
Despite the fact that Kees van Dongen was one of the most famous painters of the twentieth century, only little information about his palette and his technique is available. To contribute to the characterization of van Dongen's painting materials, La Violoniste, painted by the artist around 1922, has been analyzed by using three complementary techn...
Article
British 19th century painters such as J. M. W. Turner, commonly modified the properties of their paint by using gels called “gumtions”. These gels allowed them to easily tune the paint handling and drying properties. The fascinating properties of these “gumtions” were obtained by adding lead acetate to a ternary system based on mastic resin, linsee...
Article
Colour was a key feature of Greek and Roman sculpture, but due to the current bare-marble appearance of many such statues, it is now frequently overlooked. This is illustrated here by the first study of polychromy in Roman statues from the province of Africa Proconsularis. Five sculptural fragments dating to the second and third centuries AD were e...
Article
British 19th century painters such as J. M. W. Turner, commonly modified the properties of their paint by using gels called "gumtions". These gels allowed them to easily tune the paint handling and drying properties. The fascinating properties of these "gumtions" were obtained by adding lead acetate to a ternary system based on mastic resin, linsee...
Article
Full-text available
The chemical composition of sandarac resin was investigated qualitatively and quantitatively by gas chromatography-mass spectrometry (GC-MS). Six compounds with labdane and pimarane skeletons were identified in the resin. The obtained mass spectra were interpreted and the mass spectrometric behaviour of these diterpenoids under EI conditions was de...
Article
The colorful decoration of statues and buildings in antique times is commonly described by the term Antique Polychromy. It is well known among scholars but less so in the interested public and its exact form is subject of ongoing research. In this paper we discuss results obtained from the Frieze of the Siphnian Treasury from the Sanctuary of Delph...
Article
The painting Rebecca and Eliezer at the Well, which hangs in the Fitzwilliam Museum, Cambridge, UK, is possibly one of the last figure painting executed by Nicolas Poussin at the very end of his life and is usually dated to the early 1660s. In this perspective special feature, Philippe Walter, Alain Brunelle and colleagues give new insights on the...
Article
Full-text available
The origin(s) and role(s) of metal soaps in paints are a worldwide concern today. These hybrid compounds, containing both fatty acid chains and metals associated with a carboxylate function, are increasingly identified in paints. As reviewed in the first part of this work, the presence of metal soaps in paints is differently interpreted in scientif...
Conference Paper
Optical instruments for space applications with improved performances (smaller pixels and spectral range extension) are becoming more and more sensitive to chemical contamination and particle sedimentation. Outgassing under vacuum conditions causes dramatic flux losses, especially in the UV bandwidth. Furthermore, it is difficult to perform physico...
Article
Time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging using cluster primary ion beams is used for the identification of the pigments in the painting of Rebecca and Eliezer at the Well by Nicolas Poussin. The combination of the high mass resolution of the technique with a sub-micrometer spatial resolution offered by a delayed extraction...
Article
Lead compounds have been commonly used since the Renaissance period to increase the drying properties of oils. This article presents new insights on the mechanisms involved: Fourier transform infrared spectroscopy (FT-IR) has been used to investigate the effects of lead oxide on the drying process of linseed oil. The changes occurring during the dr...
Article
Full-text available
Carbon black materials have been frequently used from prehistory as pigments for drawings and paintings and also as dyes, inks and cosmetics, since they are easy to make by burning organic matter. However, the carbonaceous phases they form are often ill-ordered and not easy to characterize. Five carbon black Roman micro samples found in vessels in...
Article
Carbon black materials have been frequently used from prehistory as pigments for drawings and paintings and also as dyes, inks and cosmetics, since they are easy to make by burning organic matter. However, the carbonaceous phases they form are often ill-ordered and not easy to characterize. Five carbon black Roman micro samples found in vessels in...
Article
Full-text available
The identification of dyes in archaeological remains is a long standing challenge. Major problems include contamination by environmental conditions over long periods of time, small amounts and limited availability of excavated samples, and low concentrations of dyestuff in the obtained samples. To address these issues, highly sensitive and non-dest...