0000000000073744

AUTHOR

D. Juanes

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…

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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…

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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…

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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…

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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…

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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.

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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…

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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…

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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…

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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…

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