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The painting studied, featuring the Virgin contemplating the sleeping Child, is a well-known composition in the religious context, especially popular since the 16th century. The technique, oil on copper plate, and materials were examined applying a multimethodological non-invasive approach. The main goal was to quantitatively characterize the layer composition and thickness. To obtain them, X-ray fluorescence spectroscopy coupled with Monte Carlo simulation was used for the first time, to the best of our knowledge, for this kind of object. This technique was also integrated with more conventional photographic and spectroscopic techniques such as multiband imaging (MBI), Raman spectroscopy, external reflection Fourier transform infrared spectroscopy (ER FT-IR), and optical microscopy. The obtained data showed the use of a background based on lead white, a wide palette, which includes azurite, vermilion, lead white, and some ochers, and documented the conservation status. Although the investigations contended with the object's complexity, the results demonstrate the efficacy of the XRF–Monte Carlo simulation approach in characterizing the materials constituting the artwork in a totally non-invasive way. [ABSTRACT FROM AUTHOR]

This paper describes the results obtained from an archaeometric study of a bronze Nuragic small boat model (Sardinia, Italy) dating from the Early Iron Age (presumably 9th–7th centuries BC). The artifact comes from an unknown location in Sardinia and is one of the objects that came to the Museum of Turin in the 19th century. This model is of particular interest as it is a unique Nuragic boat model containing a human figure among its decorations. The artifact is kept in the collection of the Royal Museum of Turin (Italy) and is a typical example of Sardinian manufacture from the Early Iron Age. This study was carried out using a combination of non-invasive techniques with energy dispersive X-ray fluorescence spectrometry (ED-XRF) integrated with Monte Carlo (MC) simulations and Raman spectroscopy, which allowed the characterization of the alloy of the artifact. [ABSTRACT FROM AUTHOR]

The Moche civilization in Peru developed marvelous metallurgy, primarily using alloys of gold, copper and silver, with the most famous of them called Tumbaga, which resembles pure gold after a depletion process on its surface. However, they also created objects with more standard single-layer alloys or gilding. To distinguish between these techniques in a non-destructive manner is essential. Here, we analyzed a thigh protector, composed of two parts, one seemingly in silver and the other seemingly in gold. The sample was analyzed using X-ray fluorescence measurements integrated with Monte Carlo simulation. The results show that the silver part is formed of a silver-based alloy covered in a corrosion layer, while the gold part is made of Tumbaga. Moreover, for the first time, the gold profiles of different Tumbaga gold objects, from the same burial, were compared, allowing us to obtain information about the standardization of their manufacture. [ABSTRACT FROM AUTHOR]

Depleted metals have been produced since many centuries ago. Probably the most famous examples from ancient times are the so-called Tumbaga gold artifacts, whose production was introduced by the pre-Colombian civilizations. Tumbaga-like structures have been identified also in modern nanotechnological materials. In both cases, but specially for the ancient Tumbaga, due to their preciousness, their characterization should be obtained by non-destructive analysis. Several analytical protocols have been developed, some of them non-destructive, such as those based on X-ray Fluorescence, but the results obtained do not always allow for a reliable identification of Tumbaga with respect to gilding or single alloy samples. Besides the capability to distinguish between different structures of the sample, it is also important to obtain a quantitative estimation of its composition. In order to meet this demand, a new approach based on X-ray Fluorescence coupled to Monte Carlo simulations is proposed. It allows one to distinguish easily between the three manufacturing techniques and to quantify the composition of the sample without any destructive sampling. It constitutes a new tool for the study of complex alloy structures. The protocol is applied here to some ancient Tumbaga gold samples and is described in detail, comparing the results to those obtained with other techniques. [ABSTRACT FROM AUTHOR]

The Nuragic civilization (Sardinia, Italy, XVIII–VIII B.C) developed a flourishing bronze metallurgy with strong connections with other civilizations from the Mediterranean basin. Within the large bronze production, there are some peculiar representations of human figures, known in the archaeological environment of Sardinia as bronzetti, depicting warriors, priests, and offerers. In this paper, an interesting couple of Nuragic statuettes representing offerers, one from the Pigorini Museum in Rome and another from the Musei Reali in Turin, were analyzed. They have been investigated with X-ray fluorescence integrated with Monte Carlo simulations (XRF-MC). The combined methodology provides more accurate results, ranging from the structural characterization to the identification of the corrosion layers to the estimation of the composition of the alloy of the artifact. One of the most striking results regards the heads of the offerers: both heads are covered with a thick iron-based layer, even though the whole artifacts are made of a copper alloy. To understand the reason behind this peculiar corrosion patina, several hypotheses have been considered, including the possibility that these iron mineralizations are the consequence of an ancient superficial treatment, intending to confer a chromatic effect on the figurine's head. [ABSTRACT FROM AUTHOR]

From the availability of metals to the technology and tools needed to transform them, roughly every civilization in the Mediterranean basin has a metalsmith story. Many of the objects produced by them share a few peculiar characteristics, usages, or even shapes. In this scenario, a class of objects that can be clustered by their usage, i.e., working tools, stands out from the crowd. For this study, a set of working tools from the Nuragic civilization (Sardinia, Italy) was researched with a non-destructive technique: X-ray Fluorescence (XRF). A quantification of the chemical species present in their alloy was obtained with the use of Monte Carlo simulations. The XRMC package, used for the simulations, managed for the first time to reproduce very complex corrosion layers and to thoroughly characterize them from a chemical perspective. The obtained results were discussed and compared to other results reported in the literature. [ABSTRACT FROM AUTHOR]

A by‐product of energy‐dispersive X‐ray fluorescence (EDXRF)‐analysis consists of using the ratios of selected X‐ray peaks to determine the thickness of multilayered objects. Three different methods were developed in the past, all because the two main K or L X‐lines from an EDXRF spectrum emitted by a chemical element have a distinct energy and are differently attenuated by an overlying layer. This specific subject has many papers dedicated, but only a few considerations were devoted to the limits of these methods, that is, the range, for example, of gold thickness that can be usefully determined by each method. This paper defines these limits in the specific case of thin gilding (with d < 1 μm). Three typical situations were considered, and the following artefacts were studied: two artefacts on gilded lead, where the gold leaf is superimposed to a white lead pigment, both in the painting "La Fornarina" of Raphael, dated 1520 AD, and in the imperial carriage of Dom Pedro II emperor of Brazil. In this last case, the white lead pigment was painted over the wood structure of the carriage; four artefacts on gilded copper, three crowns and a pendant, from the tomb of the Lady of Cao, from the Moche civilization of the North of Peru, dated around 350 AD; finally, an artefact on gilded silver, a vase from the Chavín civilization of the North of Peru, dated around 1000‐200 BC. [ABSTRACT FROM AUTHOR]

The outdoor sculpture of the first Portuguese king, D. Afonso Henriques (c. 1109–1185 AD), placed in Guimarães (North Portugal), is one of the most emblematic national sculptures. Created in 1887 by António Soares dos Reis, it possesses a remarkable symbolic value in the presumed birthplace of the king. In addition to the artistic and heritage importance of the monument, it is one of the few sculptures cast by a Portuguese industrial foundry in the 19th century. This study obtained data on the sculpture's elemental composition and corrosion products, gathering important historical and technical information. For this purpose, a multi-analytical approach consisting of X-ray fluorescence (XRF), X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM-EDS) was carried out to characterise the bulk metal and corrosion layers. The data revealed a ternary alloy of Cu, Sn and Zn, with Pb, Fe, As, Bi and Mn as minor elements. The alloy matches that of other sculptures cast in that period. In terms of corrosion, it is characterised by the presence of oxides. These results represent the first step for applying an appropriate conservation strategy for bronze sculptures with similar characteristics. [ABSTRACT FROM AUTHOR]

The high artistic and cultural relevance of particular objects, in this case from the Nuragic civilization, have stimulated the growth of a forgery industry, replicating small bronze boats (navicelle), statues (bronzetti), and other objects. It is often the case where the forgeries are of such quality that it becomes difficult to distinguish them from authentic artifacts without a proper chemical analysis. In this research, a Monte Carlo simulation algorithm for X-ray interactions with matter is used to obtain the chemical composition from the bulk of each object from a set of five. The method employed has the advantage of being completely nondestructive and relatively fast. The objects' chemical composition and morphology were compared with the data available from authentic artifacts so their authenticity could be inferred. Four of the five objects are likely to be authentic, where two of them could be associated with a Sardinian origin. [ABSTRACT FROM AUTHOR]

Miniaturized bronze flasks represent a small portion of a wide metallurgical production that flourished in Sardinia (Italy) between the Final Bronze Age (FBA) and the Early Iron Age (EIA). They replicate a well-known and symbolic type of object, the pilgrims' flask, common in all Europe and Mediterranean basin, and have but few archaeological parallels. For these reasons, their characterization can be considered important from an archaeological perspective. Three flasks, preserved at the Antiquarium Arborense museum (Oristano), were analyzed by X-Ray Fluorescence Spectroscopy (XRF) and Raman spectroscopy, integrated by multispectral images. The samples, coming from illegal excavations, posed two problems: establishing their authenticity and investigating the alloy composition of such particular objects. All specimens presented a widespread degradation in the outer surface: XRF and Raman spectroscopy indicated the presence of copper oxides, calcium and copper carbonates deposits. The abscence of Zn, a clear marker of forgeries, was not detected by XRF. In two of the flasks, an unusual Sn content above 20%, was detected. For FBA and EIA, especially regarding southern Europe, Sn was extremely rare, and was possibly used with caution. Further results are presented herein. [ABSTRACT FROM AUTHOR]

Featured Application: Characterization of surfaces in multilayered structures is a requirement in many application areas. Such characterization should be nondestructive, and, in some cases, it must be performed in situ. This is the case of precious Cultural Heritage samples. The use of X-ray fluorescence analysis is currently one of the few solutions. When a large surface must be characterized, a MA-XRF scanning system can also be employed. The use of X-ray fluorescence (XRF) scanning systems has become a common practice in many application sectors. In multistratified and heterogeneous samples, the simple analysis of an XRF spectrum as a response of the entire sample is not reliable, so different spectral analysis techniques have been proposed to detect the presence of surface stratification. One commonly studied case is that of gilding, i.e., the presence of a superimposing gold-leaf layer. The observation of changes in the net peak ratios of a single element or of several elements in an XRF spectrum is a well-developed practice, but is still not used in the case of XRF scanning (macro-X-Ray fluorescence scanning, MA-XRF), a technique that can be described as the extrapolation of XRF spot analysis to a second dimension, scanning a sample surface instead. This practice can yield information on the overlaying layer thickness, if some properties of the sample are known—or estimated—beforehand, e.g., the overlapping layer's chemical composition and the matrix effect contribution from the bulk material (thick ratio). This work proposes the use of an algorithm to calculate the thickness distribution of a superimposing gold layer accurately and automatically through the differential attenuation method by using MA-XRF datasets in a total noninvasive manner. This approach has the clear advantage over the traditional spot sampling of allowing the generation of a surface heightmap to better visualize and interpret the data, as well as a considerably larger sample space. Monte Carlo simulations were used to verify the influence of the medium used to adhere the gold leaves to the substrate and to generate known spectra to assess the algorithm's accuracy. [ABSTRACT FROM AUTHOR]

This work is part of a broader research line that aims to develop and implement a nondestructive methodology for the chemical characterization of archaeological metals based on a protocol that combines energy dispersive X-ray fluorescence spectrometry (ED-XRF) with a Monte Carlo (MC) simulation algorithm. In this paper, the ED-XRF-MC protocol has been applied to estimate the chemical composition of a selected group of 26 copper-based artifacts and fragments recovered at Perdigões, one of the larger Chalcolithic sites of southwest Iberia. All the analyzed artifacts have a multilayered structure composed of the alloy substrate and of a superficial layer common in each metal buried for hundreds of years and consisting of the patina mixed with soil. Due to the difficulty in determining the quantitative composition of these alloys in the presence of this complex patina/encrustation layer, the spectrometric protocol applied in this paper allows to simulate and to determine the composition of the bulk alloy without any prior removal of the overlying corrosion patina layer and soil-derived crust, even in the presence of rough and irregular surfaces, thus preserving the physical integrity of the artifacts. The overall results obtained with the ED-XRF-MC protocol indicates that the artifacts from Perdigões are almost pure coppers with a low amount of arsenic (<3.0 wt%) and reduced concentration of elements such as Pb, Bi, and Sb, in agreement with the third millennium metallurgy known in southwestern Iberia. Also based on previously theoretical–experimental studies, the data presented in this paper show how the applied analytical methodology can be a fast and completely nondestructive analytical tool reliable for routine and large-scale chemical analysis of archaeological metals, thus representing a major advance to be broadly applied within the field of cultural heritage studies. [ABSTRACT FROM AUTHOR]

The chemical composition of a unique bronze artifact known as the “ Cesta ” (“Basket”) belonging to the ancient Nuragic civilization of the Island of Sardinia, Italy has been analyzed by combining X-ray Fluorescence Spectroscopy (XRF) with Monte Carlo simulations using the XRMC code. The “ Cesta ” had been discovered probably in the XVIII century with the first graphic representation reported around 1761. In a later draft (dated 1764), the basket has been depicted as being carried upside-down on the shoulder of a large bronze warrior Barthélemy (1761), Pinza (1901), Winckelmann (1776) . The two pictorial representations differed only by the presence of handles in the most recent one. XRF measurements revealed that the handles of the object are composed by brass while the other parts are composed by bronze suggesting the handles as being a later addition to the original object. The artifact is covered at its surface by a fairly thick corrosion patina. In order to determine the bronze bulk composition without the need for removing the outer patina, the artifact has been modeled as a two layer object in Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

Many objects of common use (tools, utensils, metals, knick-knacks, dishes and glasses) and artifacts (for example paintings of all types) are composed of two or more layers. In many cases, it would be useful to determine the correct location, composition and thickness of the various layers. Non-destructive and non-invasive methods are described, based on energy-dispersive X-ray fluorescence which are able to 'reconstruct' the complete structure of a multilayered sample. These methods use, in different ways, the ratios of characteristic X-rays emitted by the elements of the layers, and, in particular, two effects can be usefully employed, effects which are based on the differential attenuation of Kα and Kβ or Lα and Lβ X-rays: Different self-attenuation of K or L X-rays emitted by an element characterizing a layer because of the different energy of the two K or L X-rays;, Different attenuation of the two K or L X-rays of an element characterizing a layer by a second superimposed layer., Furthermore, the ratio of the Kα (or Lα) X-rays emitted by an element characterizing the internal layer, to the Kα (or Lα) X-rays emitted by an element characterizing a second superimposed layer, can also be employed in the 'reconstruction' of the layers. In this paper, the theoretical background of all these methods is described, and typical examples are shown. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The analytical study of Cultural Heritage objects often requires merely a qualitative determination of composition and manufacturing technology. However, sometimes a qualitative estimate is not sufficient, for example when dealing with multilayered metallic objects. Under such circumstances a quantitative estimate of the chemical contents of each layer is sometimes required in order to determine the technology that was used to produce the object. A quantitative analysis is often complicated by the surface state: roughness, corrosion, incrustations that remain even after restoration, due to efforts to preserve the patina. Furthermore, restorers will often add a protective layer on the surface. In all these cases standard quantitative methods such as the fundamental parameter based approaches are generally not applicable. An alternative approach is presented based on the use of Monte Carlo simulations for quantitative estimation. [ABSTRACT FROM AUTHOR]

X-ray fluorescence (XRF) is a well known nondestructive technique. It is also applied to multilayer characterization, due to its possibility of estimating both composition and thickness of the layers. Several kinds of cultural heritage samples can be considered as a complex multilayer, such as paintings or decorated objects or some types of metallic samples. Furthermore, they often have rough surfaces and this makes a precise determination of the structure and composition harder. The standard quantitative XRF approach does not take into account this aspect. In this paper, we propose a novel approach based on a combined use of X-ray measurements performed with a polychromatic beam and Monte Carlo simulations. All the information contained in an X-ray spectrum is used. This approach allows obtaining a very good estimation of the sample contents both in terms of chemical elements and material thickness, and in this sense, represents an improvement of the possibility of XRF measurements. Some examples will be examined and discussed. [ABSTRACT FROM AUTHOR]

Abstract: Generally, quantitative X-ray fluorescence (XRF) analysis estimates the content of chemical elements in a sample based on the areas of the fluorescence peaks in the energy spectrum. Besides the concentration of the elements, the peak areas depend also on the geometrical conditions. In fact, the estimate of the peak areas is simple if the sample surface is smooth and if the spectrum shows a good statistic (large-area peaks). For this reason often the sample is prepared as a pellet. However, this approach is not always feasible, for instance when cultural heritage or valuable samples must be analyzed. In this case, the sample surface cannot be smoothed. In order to address this problem, several works have been reported in the literature, based on experimental measurements on a few sets of specific samples or on Monte Carlo simulations. The results obtained with the first approach are limited by the specific class of samples analyzed, while the second approach cannot be applied to arbitrarily irregular surfaces. The present work describes a more general analysis tool based on a new fast Monte Carlo algorithm, which is virtually able to simulate any kind of surface. At the best of our knowledge, it is the first Monte Carlo code with this option. A study of the influence of surface irregularities on the measured spectrum is performed and some results reported. [Copyright &y& Elsevier]

We conducted an X-Ray Fluorescence investigation on bone fragments belonging to King Peter III of Aragon and Queen Blanche of Anjou. The spectroscopic analysis was carried out in selected points of the bone fragments. Several transitional elements normally unexpected in the bone composition have been found at varying level of concentration. The presence of these elements was interpreted in relation to chemical treatments for mummification of bodies as well as to dietary habits, including tools used for cooking and for the consumption of food. [ABSTRACT FROM AUTHOR]

A Roman bronze statuette from the 2nd Century BC was recovered from a nuragic sanctuary close to Florinas, in the north of Sardinia. The facial portion of the statuette is covered by a silver mask, partially gilded and attached to the bronze by tin-lead welding. The silver mask was carefully analyzed by portable energy-dispersive X-ray fluorescence (EDXRF), a non-destructive and non-invasive method. The aim of the analysis was to reconstruct the layered structure of the silver gilt mask, and to determine homogeneity and thickness of the gold, silver and lead–tin sheets. This is possible by using the internal ratio of the X-ray lines, i.e. starting from the surface, Au (L α/L β), Ag (K α/K β), Au-L α/Ag-K α and Pb (L α/L β).The results were compared with those obtained with simulated X-ray spectra, obtained both experimentally and by using the Monte Carlo simulation technique. [ABSTRACT FROM AUTHOR]

A simple, fast, and nondestructive analytical methodology combining X-ray Fluorescence (EDXRF) and Back-scattered Electron Microscopy coupled with Energy Dispersive Spectroscopy (BSEM+EDS) has been applied to characterize the alloy’s composition of ex-votos metal statuettes of unknown provenance and age stored in the Museum of Évora in Southern Portugal, and to compare it with Iron-Age artefacts of similar typology recovered from the well-known Phoenician settlement (7th century BC) of Alcàcer do Sal located about 50 km W of Évora. The aim of the study was two-fold: (a) to confirm the age and provenance of the bronzes from the Alcàcer settlement; (b) to assess whether the combined archaeometric approach could shed light on the interaction between local (Iberian peninsula) and allochtonous (Phoenician) technological know-how and on how the “Orientalizing” Phoenician influence had been modulated locally in the making of metal artifacts. In this respect, for comparative purposes, selected bronze statuettes displaying “Orientalizing” features of inferred Phoenician origin from the Nuragic collection of the National Archaeological Museum in Cagliari and the G.A. Sanna Museum of Sassari, Sardinia, were also analyzed by EDXRF. Results indicate that all statuettes are made of an alloy of Cu/Sn or Cu/Sn/Pb with variable Sn and Pb content. The presence and content of Pb and of Fe (the latter always >0.05 %) in the alloy suggest a production technology involving the smelting of ferrous minerals and/or the use of reducing firing conditions with locally available Pb intentionally added as fluxing agent. The alloy’s compositional data is consistent with a provenance of the Évora statuettes from the known Phoenician settlement of Alcàcer do Sal in Southern Portugal. [ABSTRACT FROM AUTHOR]

Abstract: This work presents the recent developments of xraylib, an ANSI C library that provides convenient access to a large number of X-ray related databases, with a focus on quantitative X-ray fluorescence applications. The enhancements include improved X-ray fluorescence production cross sections that take into account cascade effects and M-lines, as well as revised line energies, atomic level widths, Compton broadening profiles etc. A full overview of the complete application programming interface is presented. [Copyright &y& Elsevier]

A portable EDXRF equipment was employed to analyze pre-Columbian metals (gold, silver and copper objects) and to determine the thickness of gold in the case of gildings. To this aim, the EDXRF equipment was optimized to detect Cu, Au and Ag, and various methods were developed to determine from X-ray spectra (K-lines ratio) the thickness of the gildings. These methods were first tested to measure gilding compositions and thicknesses of pens and decorative objects. Then pre-Columbian metals were analyzed, such as gold, silver, copper, gilded copper and gilded silver objects from the Royal Tomb of Sipán and from the Museum of Sicán, in the north of Peru. [ABSTRACT FROM AUTHOR]

A modular X-ray scanning system was developed, to fill in the gap between portable instruments (with a limited analytical area) and mobile instruments (with large analytical areas, and sometimes bulky and difficult to transport). The scanner has been compared to a commercial tabletop instrument, by analysing a Portuguese tile (azulejo) from the 17th century. Complementary techniques were used to achieve a throughout characterisation of the sample in a complete non-destructive approach. The complexity of the acquired X-ray fluorescence (XRF) spectra, due to inherent sample stratigraphy, has been resolved using Monte Carlo simulations, and Raman spectroscopy, as the most suitable technique to complement the analysis of azulejos colours, yielding satisfactory results. The colouring agents were identified as cobalt blue and a Zn-modified Naples-yellow. The stratigraphy of the area under study was partially modelled with Monte Carlo simulations. The scanners performance has been compared by evaluating the images outputs and the global spectrum. [ABSTRACT FROM AUTHOR]

• Multianalytical study of a Moche funerary mask. • ED-XRF characterization of the metal alloy with Monte Carlo simulation. • Characterization of adhesive material and its components belonging to Moche culture. • Py-GC/MS and GC/MS were used for the chemical characterization of adhesive material. • SEM-EDS and ATR-FTIR were applied to characterize inorganic filler. The aim of this paper is to characterize materials belonging to one of the masks coming from the Lord of Ucupe's tomb in the region of Lambayeque in Peru. The mask belongs to the Moche culture which lived in the north of Peru since 100 CE. Along with the study of the extraordinary metal alloy technique using X-ray fluorescence (ED XRF) integrated with the Monte Carlo simulation, this paper investigates the blackish material used as an adhesive for its inlaid eyes. This material was analysed through the ATR FT-IR and characterized through Py-GC/MS and GC/MS for the organic components and SEM-EDS for the inorganic components. The chemical characterization of the adhesive material coming from this type of artefact, based on our knowledge of current literature, is the first on this material and allows us to take a further step into the understanding of the constituents used for this purpose. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A combined investigation by X-ray fluorescence (XRF), Fourier Transform Infrared spectroscopy (FT-IR), Raman spectroscopy and powder X-ray Diffraction (XRD), supplemented with the Rietveld analysis, was conducted on sixty Spanish dinosaur bone specimens from Upper Jurassic/Lower Cretaceous to Upper Cretaceous age to investigate taphonomy and diagenetic processes. The diffraction approach assessed in all specimens the presence of fluorapatite at various levels of percentage as the mineral phase constituting the fossil bone. In addition to fluorapatite, calcite and quartz were also found as main secondary phases in many specimens. The infrared spectra of fossil bones show significant changes in the phosphate and carbonate band intensity with respect to a non-fossil bone. Conversely, the X-ray fluorescence spectra turned out to be mainly dominated by the presence of Ca, obviously accompanied by phosphorus. Simultaneously, other elements accompanying Ca, such as Fe and Sr were found at significant concentration levels. A considerable amount of Fe and Sr ions were incorporated in the structure of fluorapatite, but when their concentration was found elevated in the fluorescence spectrum, the diffraction data revealed the presence of goethite (FeOOH) and celestite (SrSO4) phases. While the X-ray diffraction phase analysis also revealed the presence of kaolinite, dolomite, barite and gypsum, in some fluorescence spectra further elements like Y, As, Pb, Ti, Mn, Cr, Cu, Zn were present in concentration at trace level. The introduction/substitution of new elements with the infiltration of new phases due to diagenesis is also affecting to various extent the Raman and FT-IR spectra with modification of some bands and/or the appearance of new bands. The average crystallite size of the “apatitic” constituent phase was found to vary from a minimum of ca. 183Å to an upper level of 2107Å. No systematic relation between apatite crystallite size and age of the dinosaur bones was found that suggests a high variability of diagenetic processes affecting the growth of bone crystallites even in the same site. [Copyright &y& Elsevier]

A spectrometric protocol combining Energy Dispersive X-Ray Fluorescence Spectrometry with Monte Carlo simulations of experimental spectra using the XRMC code package has been applied for the first time to characterize the elemental composition of a series of famous Iron Age small scale archaeological bronze replicas of ships (known as the “ Navicelle ”) from the Nuragic civilization in Sardinia, Italy. The proposed protocol is a useful, nondestructive and fast analytical tool for Cultural Heritage sample. In Monte Carlo simulations, each sample was modeled as a multilayered object composed by two or three layers depending on the sample: when all present, the three layers are the original bronze substrate, the surface corrosion patina and an outermost protective layer (Paraloid) applied during past restorations. Monte Carlo simulations were able to account for the presence of the patina/corrosion layer as well as the presence of the Paraloid protective layer. It also accounted for the roughness effect commonly found at the surface of corroded metal archaeological artifacts. In this respect, the Monte Carlo simulation approach adopted here was, to the best of our knowledge, unique and enabled to determine the bronze alloy composition together with the thickness of the surface layers without the need for previously removing the surface patinas, a process potentially threatening preservation of precious archaeological/artistic artifacts for future generations. [ABSTRACT FROM AUTHOR]

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 elements from energy-dispersive X-ray fluorescence spectra, can provide important information in assessing the exact location of each layer and for calculating its thickness. The methodological approach shown may have important applications not only in materials science but also when dealing with the conservation and restoration of multi-layered cultural heritage objects where the use of a Non-Destructive techniques to determine slight chemical and thickness variations in the layered structure is often of paramount importance to achieve the best results. [Copyright &y& Elsevier]

Abstract: We examined by Rietveld refinement of X-ray Diffraction patterns a series of 61 human and animal fossil bones in an age range from present time to Middle Triassic (around 245Ma). This approach, supplemented by elemental analysis according to X-ray Fluorescence, has permitted to obtain a quantitative evaluation of the mineralogical phases in the specimens, thus allowing to reconstruct the mineralization process involved. Concerning the apatite phase, after adopting a monoclinic geometry for the unit cell, the method permits to determine with fair degree of precision the unit cell volume, which is found to decrease in relatively short geological times as a function of the fluorine substitution process for the hydroxyl group –OH. After excluding the role of a high-temperature fire treatment to the bones, it is found that a certain linear correlation may exist over the geological time scale involved between the age of the specimen and the average crystallite size. This observation permits to use the XRD pattern as an evaluation of the age of the fossil, although the stratigraphic observations, where available, remain as the main reliable source for dating such biomaterials. The uncertainty related to this age estimation may be hardly better than 15–20% in absolute, because of various assumptions involved in the XRD methodology used and in the variability of the burial environment that may be subjected to discontinuous changes over the very long time of deposition. [Copyright &y& Elsevier]