Identification of plant cells in black pigments of prehistoric Spanish Levantine rock art by means of a multi-analytical approach. A new method for social identity materialization using chaîne opératoire
We present a new multi-analytical approach to the characterization of black pigments in Spanish Levantine rock art. This new protocol seeks to identify the raw materials that were used, as well as reconstruct the different technical gestures and decision-making processes involved in the obtaining of these black pigments. For the first of these goals, the pictorial mat- ter of the black figurative motifs documented at the Les Dogues rock art shelter (Ares del Maestre, Castello ́ n, Spain) was characterized through the combination of physicochemical and archeobotanical analyses. During the first stage of our research protocol, in situ and non- destructive analyses were carried out by means of…
Identification of overglaze and underglaze cobalt decoration of ceramics from Valencia(Spain) by portable EDXRF spectrometry
The purpose of this work is the application of non-destructive analysis to differentiate underglaze and overglaze techniques used in the decoration of glazed ceramics from Valencia (Spain). This study was carried out by portable EDXRF spectrometry using an X-ray tube and a thermoelectrically cooled semiconductor detector. From the EDXRF spectra we have identified the main elements present in the tin-opacified lead glaze and in the cobalt pigments. The identification of the underglaze and overglaze decoration is based on the different ratios between the fluorescence line of the main component of the glaze (Pb-La line) and the fluorescence lines of the main components of the pigment (Co-Ka, M…
X-ray fluorescence analysis of yellow pigments in altarpieces by Valencian artists of the XV and XVI centuries
Abstract XRF analysis has allowed a quick and precise detection and identification of the inorganic elements that compose the yellow pigments in altarpieces of the XV and XVI centuries painted by the Valencian artists Miguel Alcaniz, Vicente Macip, Juan de Juanes, Hernando Yanez de la Almedina and Hernando Llanos. The analyses have been carried out with an XRF portable system that consists of a tube of X-rays and detectors of Si(Li) and cadmium zinc telluride. This system has enabled a non-aggressive and non-destructive analysis of many pieces at the Museo de Bellas Artes of Valencia (Spain). Among the yellow pigments we have identified a pigment composed by lead and tin oxides named lead–t…
Identification of local and allochthonous flint artefacts from the Middle Palaeolithical site ‘Abrigo de la Quebrada’ (Chelva, Valencia, Spain) by macroscopic and physicochemical methods
This work summarizes the characterization of flint artefacts from the Middle Palaeolithic site ‘Abrigo de la Quebrada’ (Chelva, Valencia, Spain) and flint geological samples collected in the Chelva area. Additionally, some flint artefacts located outside this geographical zone were also analysed and compared with the samples from the Abrigo de la Quebrada site. Flint samples have been studied using methods of macroscopic description and physicochemical analysis [energy dispersive X-ray fluorescence spectrometry (EDXRF) and X-ray diffraction (XRD)]. Multivariate statistical analysis of the EDXRF data and the determination of the crystalline index of quartz, obtained from the XRD patterns, ar…
Monte Carlo simulation of alpha spectra in low-geometry measurements
Abstract Monte Carlo simulation of alpha spectra obtained with semiconductor detectors in low-geometry has been developed. The proposed method reproduces adequately experimental spectra of alpha emitters by taking into account the energy losses and trajectory changes of alpha particles as consequences of their interactions in the source, backing and detector.
EDXRF analysis of blue pigments used in Valencian ceramics from the 14th century to modern times
Abstract EDXRF analyses of cobalt-blue pigments were performed on 73 pieces of Valencian ceramics from the beginning of the 14th century up to the 20th century. In 67 of such samples, the pigment decoration was applied together with a tin opacified lead glaze cover on the clay body. In five samples the pigment was applied on the clay body without a glaze cover. The comparison between EDXRF spectra from coloured and non-coloured areas contains information about the pigment composition. Elements like Mn, Fe, Co, Ni, Cu, Zn and As are identified as characteristic of blue pigments; different associations of these elements were found and correlated with the chronology of the samples. The results…
La evaluación y seguimiento del estudiante de forma telemática: el proyecto Cuestionarios
En la mayor parte de las ciencias, los ejercicios practicos son la mejor manera de adquirir y evaluar, tanto conocimientos cientificos como las habilidades y competencias necesarias para su aplicacion. Es un entrenamiento que, como en el mundo del deporte, resulta imprescindible y mejora el rendimiento. La resolucion de problemas exige una gran dedicacion del profesorado y, en este aspecto, la utilizacion de cuestionarios on-line puede ser de gran ayuda. Sin embargo, este tipo de cuestionarios tambien presentan una dificultad, que es el esfuerzo inicial necesario. Para reducir esta dificultad se planteo la elaboracion de una base de datos de cuestiones y un protocolo de exportacion.
Application of field portable EDXRF spectrometry to analysis of pigments of Levantine rock art
The results of the analyses of elemental composition of red and black pigments of Levantine rock art from La Saltadora rock shelters (Valltorta gorge, Castellon, Spain) are presented in this paper. Nondestructive analyses were carried out using a portable energy dispersive X-ray fluorescence (EDXRF) spectrometer developed for in situ analysis. The results revealed the strong presence of calcium in all the analyzed locations due to the contribution of the underlying calcareous bedrock and the overlying crust. Iron is the main element detected in red pigments and manganese in black pigments. Iron and calcium ratios have been found indicative of the degree of preservation of the pictorial laye…
Characterization of cobalt pigments found in traditional Valencian ceramics by means of laser ablation-inductively coupled plasma mass spectrometry and portable X-ray fluorescence spectrometry.
Abstract In this work, a comparison of the performances of laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) and portable X-ray fluorescence (XRF) spectrometry for the characterization of cobalt blue pigments used in the decoration of Valencian ceramics is presented. Qualitative data on the elemental composition of the blue pigments obtained using both techniques show a good agreement. Moreover, the results clearly illustrate that potters utilized different kinds of cobalt pigments in different historical periods. While both techniques seem suitable for the proposed task, they show different strengths and weaknesses. Portable X-ray fluorescence spectrometry is a cheaper…
TRITIUM - A Real-Time Tritium Monitor System for Water Quality Surveillance
In this work the development results of the TRITIUM project is presented. The main objective of the project is the construction of a near real-time monitor for low activity tritium in water, aimed at in-situ surveillance and radiological protection of river water in the vicinity of nuclear power plants. The European Council Directive 2013/51/Euratom requires that the maximum level of tritium in water for human consumption to be lower than 100 Bq/L. Tritium levels in the cooling water of nuclear power plants in normal operation are much higher than the levels caused by the natural and cosmogenic components, and may easily surmount the limit required by the Directive. The current liquid-scint…
Preliminary analysis of Palaeolithic black pigments in plaquettes from the Parpalló cave (Gandía, Spain) carried out by means of non-destructive techniques
Abstract Parpallo cave (Gandia, Spain) is one of the most important Palaeolithic sites in the Spanish Mediterranean region. It is characterized by a mobiliary art whose archaeological sequence covers a dilated period (26,000–11,000 BP) and includes plaquettes decorated with black and different shades of red and yellow pigments. The aim of this paper is to present the results of analyses of the nature of black pigments used in the decoration of Parpallo plaquettes. The analyses were carried out by a non-destructive technique, by means of EDXRF. Furthermore, a colorimetric data bank has been created for conservation purposes. EDXRF measurements directly identify the use of manganese black pig…
Archaeometric study of ceramic figurines from the Maya settlement of La Blanca (Petén, Guatemala)
Abstract In this article, analytical results will be presented and discussed regarding a selected set of figurines from the ancient Maya settlement of La Blanca in Peten, Guatemala. The objective is to characterize the ceramic material by two analytical complementary techniques: X-ray diffraction (XRD) and total reflection X-ray fluorescence (TXRF). The data obtained by means of both XRD and TXRF were compared and analyzed by multivariate statistical techniques in order to obtain sample groups according to their chemical composition. The results of this archaeometric study have been compared to those that have been obtained through macroscopic characterization by means of the traditional cl…
Physics demos for all UVEG degrees: a unique project in Spain
Abstract The Physics Demo Project at the University of Valencia ( www.uv.es/fisicademos ) has developed a collection of physics demonstrations to be used during lectures. It consists of more than 130 experimental demos about different physics topics. More than 30 professors borrow them whenever they lecture on physics in any of our 40 courses in 17 different science or technical degrees, involving 246 ECTS and more than 3500 students. Each demo kit with a simple experimental set displays a particular physics phenomenon. An on-line user guide highlights the main physics principles involved, instructions on how to use it and advices of how to link it to the theoretical concepts or to technica…
Comparison of total-reflection X-ray fluorescence, static and portable energy dispersive X-ray fluorescence spectrometers for art and archeometry studies
Abstract In this paper, a Total-reflection X-ray Fluorescence (TXRF), a static and a portable Energy Dispersive X-ray Fluorescence (EDXRF) spectrometers are described. Both the equipments and the techniques employed in the field of the art and archeometry are compared. Some applications in this area are presented as well. The aim of the work is to know which spectrometer is the best suited depending on the work of art and the problem treated. The conclusion reached from the experience is that the portable EDXRF spectrometer is advisable to make “in situ” and online analysis in a multidisciplinary environment, the static EDXRF equipment is good to perform analysis on paper and metal pieces a…
Colours of the « images of the floating world ». non-invasive analyses of Japanese ukiyo-e woodblock prints (18th and 19th centuries) and new contributions to the insight of oriental materials
Abstract In the Edo (1615–1868) and Meiji (1868–1912) periods, Japanese woodblock prints were a commercial form of art that reproduced the everyday life of ordinary people (the ukiyo-e style). Since different dyes and pigments were used to produce these prints, changing over time, the knowledge of these materials can be very important for the history and the conservation of ukiyo-e prints. This study will present the results of the investigation of several woodblock prints, produced between the 18th and 19th centuries. The artworks belong to the Asian art collection at the Museum of Zaragoza (Spain). The aim of the study is the identification of organic colorants and inorganic pigments empl…
RHEOLOGICAL BEHAVIOUR OF MICROCRYSTALLINE CELLULOSE HYDROGELS
ABSTRACT An extensive study was made of the rheological behaviour of microcrystal1ine cellulose-sodium carboxymethyl cellulose (MCC-NaCMC) gels at six different concentrations. The effect of agitation time, storage time, shear rate and temperature on the viscosity of these thixotropic gels was analysed, over 7200 resulting values of being available to this effect The pseudoplastic and thixotropic characteristics of the gels was established and a progressive decrease in gel viscosity with increasing storage time was observed, although retaining stability. On the other hand, constant agitation for five minutes was found to reduce gel viscosity by 40 to 50%, regardless of concentration.
IDENTIFICATION, PROCESSING AND USE OF RED PIGMENTS (HEMATITE AND CINNABAR) IN THE VALENCIAN EARLY NEOLITHIC (SPAIN)
The results of the first elemental and structural physicochemical analyses (SEM–EDX, TXRF, XRD, FTIR, GC and EDXRF) of Early Neolithic red pigment samples from the region of Valencia confirm one of the earliest uses of cinnabar (HgS) in Spain (5300 to 5000 cal bc). They also inform on the storage of massive quantities of hematite and the development of specific technologies of hematite-based paint production and use. The samples were recovered at the three most significant Early Neolithic sites of the Mediterranean coast of Spain: Cova de l'Or (Beniarres, Alacant), Cova de la Sarsa (Bocairent, Valencia) and Cova Fosca (Vall d'Ebo, Valencia), which together have provided the most important E…
Characterization and sources of Paleolithic–Mesolithic ochre from Coves de Santa Maira (Valencian Region, Spain)
Joaquin Sorolla's pigment characterisation of the paintings ‘Vision of Spain’ by means of EDXRF portable system
In this work, portable energy dispersive X-ray fluorescence (EDXRF) spectrometry was employed to the characterisation of the palette used by the Spanish artist Joaquin Sorolla (1863–1923) in the paintings ‘Vision of Spain’, a set of 14 oils on canvas painted by Sorolla between 1911 and 1919 by order of Mr Archer Huntington to decorate the library of the Hispanic Society of America (HSA) in New York. The analyses, sponsored by BANCAJA and provided by the HSA, were carried out in situ, prior to the cleaning and restoration process, while the paintings hanging on the walls of the library of the HSA. The results revealed that the paintings were made over different priming layers containing, res…
Characterization of Sorolla's gouache pigments by means of spectroscopic techniques
Abstract This paper presents the characterization of the Joaquin Sorolla's gouache sketches for the oil on canvas series “Vision of Spain” commissioned by A. M. Huntington to decorate the library of the Hispanic Society of America in New York. The analyses were focused on the identification of the elemental composition of the gouache pigments by means of portable EDXRF spectrometry in a non-destructive mode. Additionally, SEM-EDX and FTIR analyses of a selected set of micro-samples were carried out to identify completely the pigments, the paint technique and the binding media. The obtained results have confirmed the identification of lead and zinc white, vermillion, earth pigments, ochre, z…
Multi-technique characterization of gold electroplating on silver substrates for cultural heritage applications
Proceedings of the 12th European Conference on Accelerators in Applied Research and Technology (ECAART12).-- et al.
Study of inks on paper engravings using portable EDXRF spectrometry
Abstract The prints are fragile and delicate art objects that need for its examination a suitable technique for “in situ”, non-destructive and rapid analyses. The energy dispersive X-ray Fluorescence (EDXRF) spectrometry with portable instrumentation offers these analytical properties. In this work we present the EDXRF analyses of eight engravings elaborated with different techniques (etching and heliogravure) from the 17th to 20th centuries. The characterization of the paper is directly done from its EDXRF spectra, whereas the inks are characterized by the ink plus paper analysis after subtracting the background from the paper spectrum. Inorganic components of the paper engravings and inks…
An innovative multi-analytical approach based on spectroscopic and electrochemical techniques to study a complex Roman amphorae collection
Abstract An innovative multi-analytical approach for the classification of ancient pottery sherds was tested. Twenty Roman amphorae fragments belonging to different known typologies and twenty-seven unclassified ones from a complex Sagunto Archaeological Museum (Spain) collection were studied by multielement analysis (X-ray fluorescence spectroscopy and inductively coupled plasma mass spectrometry), Fourier-transform near infrared spectroscopy and voltammetry of immobilized microparticles employing a minimal amount of sample. Chemometric analysis based on principal component analysis allowed the identification of most of the unclassified samples, proving the importance and reliability of th…
Reconsidering the accuracy of X-ray fluorescence and ion beam based methods when used to measure the thickness of ancient gildings
Since at least 5000 years ago, gilding techniques have been used for decoration purposes or to make artefacts appear as made of solid gold. Investigation of ancient gildings inevitably requires measuring their thickness, which is usually done either through the observation of cross-sections or by methods such as Rutherford backscattering spectroscopy, particle-induced X-ray emission and X-ray fluorescence. Whereas the former method requires sampling, the latter ones are non-invasive and therefore preferable. These non-invasive methods, however, measure the number of atoms per unit area, which can be converted into thickness only if the density is known. So far this has not been considered a…
Analysis of pigments from Spanish works of art using a portable EDXRF spectrometer
Nowadays there is an intensive program for the conservation, restoration and analysis of the impressive and extensive Spanish cultural heritage. In the last few years, the Unidad de Arqueometria of the ICMUV has carry out a great quantity of in situ EDXRF analysis of pigments on materials of historic and cultural interest (altarpieces, frescoes, canvas, sculptures, etc.) from museums and churches of the whole of the Spanish geography. Here we present a few examples of the analysis of works of art using x-ray fluorescence spectrometry with a portable system based on x-ray tubes and a non-cryogenic Si-PIN detector. EDXRF qualitative and non-destructive analyses of stone, pigments and preparat…
EDXRF analysis of the Pentecost Triptych from the “São Pedro de Miragaia” church (Porto, Portugal)
Abstract EDXRF spectrometry was used to determine the pigment composition of the Pentecost Triptych, a Flemish masterpiece located at the Church of Sao Pedro de Miragaia (Porto, Portugal). The triptych was restored at the beginning of the 20th century and presents a great number of zones with repaints and colour alterations that can be observed on the whole of their surface. The identification of the original pigments and restoration pigments was based on their characteristic colour and the correlation between the detected elements and the named “key elements” of ancient pigments (Ca, Fe, Cu, Hg, Pb,…) and modern pigments (Ti, Ba, Cr, Zn, Co, Cd,…). The analysis of the triptych has been car…
Radioactivity measurements on migrating birds (Turdus philomelos) captured in the Comunidad Valenciana (Spain)
The radionuclides 137Cs, 134Cs and 90Sr have been measured in edible tissues and bones of migratory birds (song-thrushes, Turdus philomelos) from central and northern Europe and captured in the Comunidad Valenciana, Spain in the 1994 autumn–winter season. Eight years after the Chernobyl accident, extensive agricultural lands in Europe are still contaminated and this study shows that there was a transfer of radioactive isotopes to the captured migratory song-thrushes. The whole-body dose commitment to humans consuming these birds is estimated.
Applications of the X-ray fluorescence analysis to the cultural patrimony of the Comunidad Valenciana (Spain): Painting, metal and paper
We present examples of the application of the X-ray fluorescence (XRF) to the study of the artistic and cultural patrimony of the Comunidad Valenciana in the following areas: a) Valencian paintings of the XV and XVI centuries; b) silver ornaments coming from Iberian towns (s. III b.C.); c) ink and paper samples in manuscripts and engravings of the XVII and XIX centuries. The non destructive analyses are carried out “in situ” using a XRF system that consists of a tube of X-rays of 50 kV and 1 mA, and a detector of Si(Li) with an energy resolution 140 eV (FWHM at 5.9 keV).
Middle Palaeolithic flint procurement in Central Mediterranean Iberia: IMplications for human mobility.
Different flint types from the Middle Palaeolithic site of Abrigo de la Quebrada (Chelva, Valencia) are characterized, both macro- and microscopically, and compared with types found at other localities in the region. Although procurement predominantly concerned the immediate vicinity of sites, our results show the presence of the same types in assemblages separated by distances of up to 120 km. The long distances involved are suggestive of a pattern of North-South mobility of human groups along the coastline of central Mediterranean Iberia.
Multilayered samples reconstructed by measuring Kα/Kβ or Lα/Lβ X-ray intensity ratios by EDXRF
Abstract In this paper a general method based on energy-dispersive X-ray fluorescence (EDXRF) analysis has been tested to assess its possible use as a tool to reconstruct the structure and determine the thickness of two and/or multi-layered materials. The method utilizes the X-ray intensity ratios of Kα/Kβ or Lα/Lβ peaks (or the ratio of these peaks) for selected elements present in multi-layered objects of various materials (Au alloys, gilded Cu, gilded Ag, gilded Pb, Ag–Au Tumbaga, stone surfaces with protective treatments, Zn or Nickel plating on metals). Results show that, in the case of multi-layered samples, a correct calculation of the peak ratio (Kα /Kβ and/or Lα/Lβ) of relevant ele…
Automatic analysis of speckle photography fringes
Speckle interferometry is a technique adequate to metrological problems such as the measurement of object deformation. An automatic system of analysis of such measurements is given; it consists of a motorized x-y plate positioner controlled by computer, a CCD video camera, and software for image analysis. A fringe-recognition algorithm determines the spacing and orientation of the fringes and permits the calculation of the magnitude and direction of the displacement of the analyzed object point in images with variable degrees of illumination. For a 256 x 256 pixel image resolution, the procedure allows one to analyze from three fringes to a number of fringes that corresponds to 3 pixels/fri…
Recent evolution of the multi-isotopic radioactive content in ice of Livingston Island, Antarctica.
The temporal arrangement of the ice layers that are produced in ecosystems with perpetual snows form situations that greatly favour the study of the temporal evolution of the radioactive fallout that occurs in the said zones, whether this fallout is natural or artificial in origin. This allows one to investigate the causes of the fallout and the mechanisms transporting the radionuclides involved from their source point to the study zone, as well as their subsequent behaviour in that zone. There are special difficulties involved in this type of study in Antarctica. Some are of a general character deriving from the conditions of extreme climate and isolation which complicate the processes of …
An approximation to the study of black pigments in Cova Remigia (Castell on, Spain). Technical and cultural assessments of the use of carbon-based black pigments in Spanish Levantine Rock Art
International audience; Spanish Levantine Rock Art is a unique pictorial expression within the prehistoric European context. Located in shelters in the inland regions of the Iberian Mediterranean basin, this art form, which must be necessarily studied in the frame of the process of neolithization of this territory, still lacks direct dating, and therefore its authorship is still open to debate. In this paper we present the first characterization of black pigments used in the Cova Remigia shelters in the Valltorta-Gassulla area (Castell on, Spain) by means of EDXRF spectrometry combined with SEM-EDS and Raman spectroscopy. Our aim is both to identify the raw material used for the preparation…