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A set of 33 fragments of lustre-decorated ceramics uncovered during an archaeological excavation in Manises (Valencia, Spain) have been studied. These ceramics were produced in Manises from the 14th to the 18th century. This well-dated set of ceramic shards represents the diversity of Manises lustre production and is a complete time sequence of reference for the technological analysis. Texture analysis of the glazes has been carried out by SEM-EDAX, the inner and outer surfaces of the lustre decorations being analysed with non-destructive ion beams by PIXE and RBS, and also by high-resolution electron microscopy. The results are compared with other lustre productions and the time trend of the microstructures, glaze and lustre composition is analysed. It is concluded that Sn was used to opacify glazes until the beginning of the 17th century and that changes in the lustre microstructure occurred around 1500. [ABSTRACT FROM AUTHOR]

This paper describes microstructural analyses by X-ray portable diffraction and microdiffraction on intentional patina of the bronze museum objects from antique Egypt and the Roman Empire. They bring evidence of the presence in the true black bronze patinas of metallic gold and/or silver presumably as nanoparticles. Three other Egyptian patinas not belonging to black bronze are characterised. Apparent black patination on a Roman scalpel handle is discussed. The discovery of a new patination procedure on Roman artefacts from the Louvre museum is also related, based on intentional high temperature oxidation to obtain a dark patina on a lead bronze object. A presence of lead carbonate cerussite is an important observation. [ABSTRACT FROM AUTHOR]

Focuses on a study which discussed an electrolytic technique to introduce hydrogen into p-type silicon at room temperature. Characteristic of hydrogen that makes it suitable in the subject of semiconductors; Effect of hydrogen on acceptors in crystalline silicon; Method of introducing hydrogen.

The paper presents a comprehensive physico-chemical investigation on a series of Hispano-Moresque objects produced in the eastern Spain workshops between the XIV and XVIII centuries and fragments from XII century, in order to compare them with the Italian Renaissance majolica production. The techniques used are mainly non-destructive (ion beam analyses and X-ray diffraction), sometimes complemented by SEM observation and microanalysis, and electrothermal atomic emission spectrometry. Such methods allow a full description of the terra cotta, of the glaze and of the different surface layers which constitute the lustre decoration indicating individual elemental composition and thickness of each layer containing or not metallic nanoparticles. Principal results show the following: i) a constant source of supply for the eastern Spain terra cotta; ii) a significant change in the composition of the Spanish glazes around the XVII century, with the disappearance of the opacifying tin oxide addition; iii) significant evolutions in the structure and composition of the lustre layers, in particular related to the presence or not of a metal-free surface glaze film and its thickness; iv) interesting analogies and differences with the Italian majolica; v) confirmation of the change in the quality of blue pigment during XVI century, already evidenced by the authors in previous publications. A discussion about the transmission of the lustre technique between eastern Spain and Italy at the Renaissance period is proposed. [ABSTRACT FROM AUTHOR]

The present study proposes a complete characterisation of the liquid gold silver layer on glass, from the application of the initial product, to the final metallic film obtained. The decomposition of organometallic compounds, during the heating, has been followed using different spectroscopic methods (infrared, nuclear magnetic resonance, mass spectrometry, etc.) which were coupled with thermal analyses and microscope observations (SEM, TEM, etc.). In the present paper the steps of the formation of the film will be briefly described, and a special attention is given to the study of the adhesion mechanisms which operates at the interface between the gold film and the glass substrate. Specific adhesion tests have been performed by aging the system in controlled solutions and observing the loss of adhesion after a given immersion duration. In depth concentration profiles obtained by secondary ion mass spectrometry and Rutherford back-scattering spectrometry reveal, during the process, a migration of the precious metals into the substrate. That migration ensures a good adhesion for the film. That 'diffusion' of gold into the glass substrate does not follow the classical diffusion laws and does not seem to be the only explanation for the occurrence of a good adhesion between to two partners. The results also suggest an essential role played by flux agents as vanadium, whose interaction with the alkaline modifiers of the bulk glass constitutes a critical factor for the durability of decorations. [ABSTRACT FROM AUTHOR]

Abstract: Lustre ceramics, found in a workshop located in Triana (Sevilla), have been analysed to determine the composition of glazes including the metallic particle layers giving rise to the lustre effect. PIXE and RBS were used for the elemental composition and the sub-surface concentration profiles, respectively. Copper and silver at the origin of the lustre are detected by PIXE. RBS gives access to the detailed distribution of the elements in the surface layers. The simulation of RBS spectra confirms the occurrence of thin layers (less than 300nm) containing metallic silver and/or copper. The results are compared with those obtained on other types of lustre ceramics. [Copyright &y& Elsevier]

Frescoes are known to be the most durable form of mural painting. The traditional technique, widely used throughout history, consists of applying water-dispersed pigments on a fresh lime plaster, which hardens through a carbonation reaction. At the beginning of the 20th century, Portland cement was used by some mural artists to obtain similar painting plaster. Although involving different setting mechanisms, cement-based frescoes show the same aspect and durability as lime-based frescoes. Using microstructure characterizations of ancient frescoes (lime- or cement-based) and laboratory reconstructions, this paper offers a description of the mechanisms responsible for the adhesion of pigments and the hardening of surface. [ABSTRACT FROM AUTHOR]

The paper describes the near-surface microstructure of artistic frescoes and compares the traditional fresco technique in which the pigments are applied on a fresh lime intonaco with the more recent technique in which the lime intonaco is replaced by a fresh cement plaster. The study is performed on artworks produced at different periods: one Roman fresco fragment dated from the first century CE, samples from a Renaissance Botticelli fresco and two works by a 20th century artist, HenriMarret, one on a lime intonaco and the other on a cement plaster. A special attention is given to the nature of the pigments used, to their position and adhesion process near the surface and to the colorimetric analysis of the pieces. The characterization of the different objects (performed by optical microscopy, scanning electron microscopy and microanalysis, colorimetric measurements and X-ray diffraction) gives full information on the influence of the artist's technique on the adhesion process and durability of the coloured decoration. It is proved that fresco painting on fresh cement, although considered at the beginning as not as efficient as fresco on lime, leads to a similar mechanism of pigment adhesion and probably to a similar durability. [ABSTRACT FROM AUTHOR]

study has been realised to elucidate the first step of lustre production in Italy. With this aim in mind, an investigation was carried out on an emblematic lustred object: Baglioni’s albarello. It is conserved at Louvre museum and it is considered as one of the very first examples of lustred object produced in Italy. The characteristics of the lustred film have been determined, identifying interesting aspects that may be used to scientifically confirm the origin of this object. This study was completed by the investigation of other objects: a not lustred albarello, still decorated with the coat of arms of Baglioni’s family and a lustred plate with the coat of arms of the Montefeltro family. The two Baglioni’s albarelli are stylistically and historically considered as produced in one of the numerous workshops of Deruta. The origin of the Montefeltro’s plate, although from central Italy, is not precisely attested. In order to acquire more information, clarifying the origin and place of production of these objects, a comparison of their physico-chemical characteristics with results obtained and already published on different well-attested productions, such as Islamic, Hispano-Moresque and Italian, was carried out. For what concerns the museum objects, the use of non-destructive investigation techniques was mandatory. For this reason, ion beam techniques as PIXE and RBS have been used at AGLAE facility, as well as a new X-ray micro-diffraction equipment, at C2RMF. Moreover, the results were compared with data obtained on shards of certain production origin, by means of chemometric techniques. Some hypothesis concerning the place of production of the examined objects have been formulated. [ABSTRACT FROM AUTHOR]

Gold leaf decoration on Islamic glazed ceramics appears in the twelfth–thirteenth century in Iran. In late fourteenth century, many craftsmen were deported by Tamerlane – alias Timur-i Leng (1336–1405) – to Samarkand or Shakhrisabz in order to adorn the monuments he ordered to settle his power. Thus, gilded tiles are quite frequent in Timurid architecture and are regarded as a heritage of Iranian techniques of glaze decoration. This paper is dealing with the history of ceramic techniques and its first aim is to propose the main steps of the making process of gold leaf decoration. This study implies the combination of non-destructive surface observations and analyses such as SEM-EDS, Rutherford backscattering spectroscopy, X-ray diffraction and white light interferometry in the light of an ancient text describing the know-how. The other issue of the study is to compare the obtained data on two corpuses of sherds: Iranian vessel dating from the twelfth to thirteenth century, and architectural Timurid tiles dating from the fourteenth to fifteenth century, so as to grasp the evolution of the technique. [ABSTRACT FROM AUTHOR]

Abstract: Organo-metallic solutions called liquid gold are largely used to obtain thin gilded films which are employed for decorative, technological and functional uses. However, these films often prove to be fragile with respect to use, resulting in loss of brilliance or even eventual film removal. An understanding of the behaviour of the layers requires good knowledge of the materials themselves. The present work was undertaken to better understand the evolution of the structural properties of liquid gold as it undergoes heat-processing. Accordingly, we followed the thermal decomposition processes of liquid gold coatings and the formation of the gilded metal layer using a combination of experimental techniques. First, thermal analyses coupled with mass spectrometry and infrared spectroscopy gave information concerning the decomposition of the organic medium. It has been found that the process of film formation can be decomposed into three steps, the second of which is an abrupt transition between 300 and 350 °C. Details on this transition have been obtained using real-time X-ray Diffraction and Rutherford Backscattering Spectrometry. Above 350 °C, the microstructure of the coating is reorganized to obtain a final layer which contains particles, of the size of a few hundreds nanometers, as shown by Transmission Electron Microscopy. [Copyright &y& Elsevier]

Luster decoration of medieval and renaissance potteries constitutes one of the most important and sophisticated decoration techniques of the Mediterranean basin. Lusters consist in a thin layer of silver and copper nanocrystals immersed in a dielectric matrix. Different physical phenomena are responsible for the very brilliant and complex colored effect produced by the lusters. On one hand, according to the thickness of the thin layer, interferential effects occur giving rise to a classical iridescent effect. On the other hand, the nanostructure of the metallic compound leads to extra absorption, generally observed in the visible or near infrared, due to an external resonance associated with the excitation of a surface plasmon in the metallic particles. The position of this resonance, and so the color of the film, depends from many parameters, mainly: (1) the relative volume fraction p of the metal inclusions. (2) The mean size of the metal particle. (3) The shape of the particles and (4) the dielectric functions of the constituents. These two phenomena are not independent as the second one greatly affects the dielectric function of the film and, thus, its optical thickness. In this paper, the physical and optical properties of various lusters from Deruta and Gubbio (Italy) of the XVI century are presented. The structure and the composition of the different films have been determined by scanning electron microscope (SEM), ion beam analyses (PIXE and RBS) and low incidence X-ray diffraction. The optical properties have been determined by two different techniques: (a) hemispherical spectroscopic measurements under near-normal incidence; (b) gonioscopic measurements for a given angle of incidence and wavelength. The first one allows the determination of the effective index of refraction of the inhomogeneous layer, and the second one the determination of the bidirectional reflectance distribution function (BRDF) of the material. [ABSTRACT FROM AUTHOR]

For the first time some excellent pieces belonging to the majolica production of the great master Giorgio Andreoli from Gubbio (Central Italy) have been characterized from a chemical and structural point of view with the aim to identify the composition of both pigments and lustres. A series of particle-induced X-ray emission (PIXE), Rutherford backscattering spectrometry (RBS) and Raman analyses have been performed on some plates coming from Museo del Palazzo dei Consoli (Gubbio) and several French museums (Louvre, Musée National de la Céramique, Musée National de la Renaissance) lustred by Giorgio Andreoli and decorated by famous majolica painters such as Francesco Xanto Avelli. The three techniques are complementary and useful in the investigation of art objects since they are non-destructive. Furthermore, the low detection limits allow the identification of all elements and compounds present, and RBS allows concentration profiling, too. It is worth noticing that the examined objects are characterized by the presence of both gold and ruby-red lustres, a peculiarity of Mastro Giorgio’s technique. The measurements by PIXE and RBS have been carried out on the AGLAE accelerator at C2RMF, Louvre Palace. [ABSTRACT FROM AUTHOR]

Metal polychromy has been widely used for decorating metallic artworks from ancient antiquity. In Hellenistic and Roman periods, the famous Corinthian bronzes (Corinthium aes) are a typical example of the skill of metallurgical craftsmen striving to obtain various coloured surfaces on copper based alloys; but the existing investigations are devoted mainly to the 'black bronzes' obtained by oxidation in a wet medium of copper–gold alloys. The present study is part of a general programme devoted to research into different kinds of special surface oxidation treatments on copper alloys and their environmental behaviour. For archaeological objects, such treatments are difficult to observe, as a consequence of corrosion degradation. The examination and analysis of objects kept in the Department of Greek, Etruscan and Roman Antiquities of the Louvre Museum have evidenced the occurrence on one of them, a strigil dated from the first century AD, of a new type of decoration. The strigil is made of copper–zinc alloy, and its decoration exhibits orange-red coloured motifs visibly obtained by chemical oxidation. The present paper describes analyses performed using different techniques: microscopy, particle induced X-ray emission, X-ray diffraction, Rutherford backscattering spectrometry, micro-Raman spectroscopy, spectrophotocolorimetry and optical profilometry. The steps of the decoration process are detailed: the motifs were coloured together with the neighbouring surface. This neighbouring surface was further cleaned by a mechanical process to make the motif coloration appear. The present paper attempts to describe how the Roman craftsman obtained the decorated appearance. [ABSTRACT FROM AUTHOR]

Lustre is one of the most fascinating surface decorative effects produced on glazed ceramics. This technique seems to have been born in the ninth century in factories created by the Arabs during their conquests in the Orient (Mesopotamia, Egypt and Persia). Arab potters spread their knowhow all over the Mediterranean basin, especially Spain. Italian Renaissance potters succeeded in applying it to their production. The technique is based on a specific firing of the glazed pottery in a reducing atmosphere in the presence of metallic salts. The result is a surface layer with a metallic appearance, exhibiting various colours, from gold to brown or red. This paper provides the chemical nature and the physical structure of ancient gold like lustre layers and compares them with contemporary lustres produced by a Spanish craftsman reproducing the traditional Islamic techniques. Various analytical investigations (atomic force microscopy, high resolution SEM, particle induced X-ray emission, Rutherford backscattering, TEM, X-ray induced photoelectron spectroscopy, time of flight SIMS and grazing X-ray diffraction) were carried out as well as investigations into the coloured appearance by spectrophotometry. The results show that the lustre layer consists of silver and copper particles of nanometric dimensions dispersed in a glassy matrix. A model of the lustre formation is proposed wherein the development of a new superficial glaze is described. Comparison between ancient and modern production shows how the techniques have varied through the ages. [ABSTRACT FROM AUTHOR]

An open-air furnace has been designed to study in real time the high-temperature surface transformation of materials by Rutherford backscattering spectrometry (RBS) in external beam mode. A device previously designed for the observation of the high-temperature oxidation of galena has been re-designed in order to analyse massive samples and to reach a temperature range up to 700 °C and a better temperature regulation (±2 °C).Experiments are carried out to measure, by RBS using a 3 MeV 4He2+ external micro-beam, the dynamic growth of oxide layers in air on the surface of copper–tin alloys heated at temperatures varying from 250 to 650 °C. The results obtained demonstrate the usefulness of this approach: actually one single measurement series permits to obtain at the same time the composition of oxide layers built on the metal and their growth kinetic laws.In the particular study of bronzes, the growth kinetics obtained by this method show the large influence of tin concentration on the oxidation mechanism. These results are verified by measurements on samples oxidised in an independent closed furnace. The results show also the occurrence of different oxidation mechanisms as a function of temperature. A diffusion mechanism governs the oxidation kinetics only at some temperatures. [Copyright &y& Elsevier]