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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]

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]

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]

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]

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]