Search results for "Spectroscopy"
showing 10 items of 10293 documents
The blue enamels in the baroque decorations of the churches of Palermo, Sicily: Fe2+-coloured glasses from lime kilns
2009
Deep blue glasses coloured by octahedral Fe 2+ cations are often reported as textbook examples of blue pigmentation. However, despite the possibility of laboratory synthesis under reducing conditions, to date there are no well-reported occurrences of their production and use in the past. A thorough historical, ethnographic, mineralogical, and chemico-physical investigation of the 'smaltini di calcara' from several baroque churches in Palermo, Sicily, has revealed that the blue enamels widely used for altar decorations in the 17th and 18th centuries are actually a unique case of ancient blue glasses pigmented by divalent iron cations in distorted octahedral coordination. This mixed-alkali gl…
Electrochemical Fingerprint of Archeological Lead Silicate Glasses Using the Voltammetry of Microparticles Approach
2016
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Different methods for soluble salt removal tested on late-Roman cooking ware from a submarine excavation at the island of Pantelleria (Sicily, Italy)
2014
Abstract This paper deals with the comparative evaluation of different procedures of salt extraction designed for archaeological ceramics from submarine burial environments. The experimental work was carried out on a particular type of late-Roman cooking ware finds (Pantellerian ware) found in a shipwreck near the shoreline of the Island of Pantelleria (Sicily). The studied ceramic test-pieces were first recognised in terms of bulk characteristics (mineralogy, petrography and chemistry). SEM-EDS observation allowed verification of the presence of various secondary minerals at the surface and in the pore spaces formed after the prolonged permanence in seawater under oxidising or reducing con…
Consolidation and protection by nanolime: recent advances for the conservation of the graffiti, Carceri dello Steri Palermo and of the 18th century l…
2014
Abstract Nanolime dispersed in 2-propanol was extensively used for the consolidation of wall paintings. The knowledge of the advances of this methodology dealing with all the possible effects associated with the nanolime new material in conservation is fundamental to assess and improve the technique. In this paper, four different dispersions of Ca(OH) 2 nanoparticles were characterised by Small Angle X-rays Scattering technique (SAXS) and Transmission Electron Microscopy (TEM) in order to achieve information on size, shape, polydispersity, agglomeration, and crystal structure (by SAED patterns) of the particles. Once characterised, the dispersions were tested in two different case studies, …
Characterization of Iranian Moarraque glazes by light microscopy, SEM-EDX and voltammetry of microparticles
2008
Abstract Glazed ceramics have been traditionally used in Iran for decorating mosques and some civil historical buildings. In particular, Moarraque glazes have been extensively used in the indoor and outdoor decoration of mosques in Iran since the middle 14th century. The pieces have a complex elaboration based on a main glazed piece corresponding to the skeleton structure of the Shah Abbasi flower, which contains a number of holes, where are placed, mosaic-like, smaller glazed pieces forming a compact and single tile. The present work describes the analytical study performed on the glazes of several pieces of Moarraque tiles from the Ali Ebn Abi Taleb Mosque (Esfahan, Iran), which date back…
EDXRF analysis of blue pigments used in Valencian ceramics from the 14th century to modern times
2006
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…
Spectroscopic analysis used to uncover the original paint colour of the Helsinki Government Palace tower clock faces
2016
The paint stratigraphy of the two clock faces from the tower clock of the Government Palace in Helsinki (Finland) was analysed in order to determine their original colour before restoration works. Paint cross-section samples from both clock faces were analysed by confocal Raman microscopy and scanning electron microscopy coupled to an energy dispersive X-ray spectrometer (SEM-EDS). The results revealed the complex superimposition of paint layers applied over the original black colour. FTIR/ATR analyses proved that the original paint was prepared with linseed oil-resin media. Most likely not all of the different layer colours were visible. Some of the layers were likely to have been a primer…
Analyzing chemical changes in verdigris pictorial specimens upon bacteria and fungi biodeterioration using voltammetry of microparticles
2017
[EN] It is reported the application of the voltammetry of microparticles (VMP), complemented with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and field emission scanning electron microscopy (FESEM) techniques, to monitor the deterioration of verdigris pictorial specimens under the action of different biological agents. This methodology would be of application for identifying the type of biological agent causing deterioration of paintings, which is an important problem affecting cultural heritage. The analysis of biodeterioration processes is complicated by the fact that the action of microorganisms can affect both pigment and binding media. The deteriorat…
mtDNA analysis of the human remains buried in the sarcophagus of Federico II
2005
Abstract The sarcophagus containing the remains of Federico II, located in the Cathedral of Palermo (Sicily, Italy), was opened on 1998 to perform a multidisciplinary survey [1]. Next to the remains of Federico II and in close contact with them were laying two other skeletons belonging, according to historical records, to Pietro II di Aragona and to an anonymous person (“The Third Individual”), probably a woman. The bones appeared severely deteriorated. Chemical analysis performed on bone samples excluded that the bodies underwent some kind of embalming process. The analysis of mtDNA from bone samples taken from the three skeletons was successful in only one of the two labs involved. The HV…
Biological mineral content in Iberian skeletal cremains for control of diagenetic factors employing multivariate statistics
2013
Abstract The aim of this study was to define a strategy for a correct selection of bone samples by employing inductively coupled plasma optical emission spectroscopy (ICP-OES) for reconstructing the biological mineral content in bones through the determination of major elements, trace elements and Rare Earth Elements (REE, lanthanides) in skeletal cremains of ancient Iberians (III–II B.C), discovered in the Necropolis of Corral de Saus (Moixent, Valencia) between 1972 and 1979. The biological mineral content was determined taking into account diagenetic factors. A control method for a better reading of results was applied. To explore large geochemical datasets and to reduce the number of va…