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The silver coinage of Celtic tribes settled in northern Italy (IV–I century B.C.) is a topic characterized by several issues, such as chronology, attributions and relationships between emissions produced in different periods. In order to provide numismatists with new data, several specimens, belonging to different typologies, have been analysed with neutron diffraction technique to overcome surface alteration and to provide bulky compositional and structural information of the coins. Measurements performed with the INES diffractometer at the ISIS facility provided essential data for numismatics research. A clear silver debasement occurring between the first and latter emissions has been traced, due to inflation processes which can be related with the increasing power of Roman Republic in the Cisalpine region. Moreover, compositional data enabled for the first time to identify internal evolutions inside typologies defined by numismatists. The silver loss has also been used to establish a relative chronology between different emissions. Other parameters such as texture index, residual strains and grain dimensions have been useful to understand technical aspects of minting procedures during Iron Age.

X-ray fluorescence (XRF) is a well-known technique for the analysis of ancient metals. Thanks to the availability of portable instruments (p-XRF), it is extensively used for the chemical characterization of coins directly in museums. In this work, the potentialities of the technique have been investigated, through its application to a case study concerning the Cisalpine Gaul coinage. More than 200 drachmas have been analysed to discriminate different productions on the base of minor elements. Major elements, on the other hand, have been used to trace alloy changes through the centuries. As concerns the quantification of the silver content (fineness), XRF and neutron diffraction results have been compared, in order to check the presence of surface-enriched layers.

The measurement of the fineness of debased ancient silver coins has proven to be a very difficult issue, which has been studied for a long time. In this paper, this subject is analysed, and the various consequences of the silver surface enrichment (SSE) are discussed exploiting the most recent investigations. A new model is proposed for the complex ob- ject that is an ancient-debased silver coin, based on the silver profiles measured on some sectioned specimens. The model is applied to a sample of 43 coins, mainly Roman victoriati, Cisalpine and Illyrian drachms (from late III to I century B.C.). The coins are investigated in two different ways: neutron diffraction (ND) and specific gravity (SG). The results of the two measurements are combined via the proposed model to provide a more complete numismatic information of the original fineness of the monetary alloy. As a result, a relation between SSE thickness and SG is derived, which, for these coinages, allows to estimate the original alloy silver content from a simple SG measurement; the same method can be used to study other debased coinages, provided that all the procedure (ND and SG) is applied

Within the neu_ART project, funded by Regione Piemonte (Italy), a team of specialists in different scientific fields coming from Istituto Nazionale di Fisica Nucleare (INFN), Physics Department of University of Torino and Centro Conservazione e Restauro (CCR) “La Venaria Reale” has developed a new digital X-ray apparatus expressly designed for painted canvas and panels up to about 3 m × 4 m. Compared to all other systems scanning time is faster, the procedure to obtain the whole radiography is easier and images are available in real time. This apparatus has been widely tested on artworks restored at CCR “La Venaria Reale”, allowing to study and optimize the operating parameters and to evaluate its performance, thanks to the feedback provided by professionals involved in the activities of conservation. Supported by the results presented in this work, restorers had the possibility to investigate the materials characteristics and to plan the operating strategy in advance: indeed, radiographs revealed areas with losses of paint, repainted areas, canvas damages, hidden pictures, writings and previous restorations. The X-Ray system for Digital Radiography is integrated in a more complex apparatus that can be used also for computed tomography of voluminous objects up to 2.5 m in height and 2 m in width, making the apparatus developed in the neu_ART project a unique and comprehensive tool at conservators' disposal.