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PEPAdb (Prehistoric Europe’s Personal Adornment Database) is a long-term, open-ended project that aims to improve access to archaeological data online. Its website (https://pepadb.us.es) publishes and analyses datasets about prehistoric personal adornment, drawing on the results of various research projects and bibliographic references.

Sputtering of silicon in a Helium magnetron discharge has been reported as a bottom-up procedure to obtain amorphous Si films containing high amounts of gas-filled nanopores. Here we compare the microstructure and composition of Si–He nanocomposite films deposited by magnetron sputtering (MS) with 4He in DC or RF and 3He in RF operation modes. Electron microscopy (SEM and TEM), X-ray diffraction (XRD) and ion beam analysis (IBA) have been used to analyze the films and to investigate the in-situ and ex-situ thermal evolution. Depending on deposition conditions different in depth compositions, nanopore size and shape distributions, porosity and He content could be obtained. The presence of impurities (i.e. oxygen) has shown to promote He diffusivity reducing He accumulation. The start temperature of He-release varied in the range 473–723 K without films crystallization. Films grown in RF mode reached contents of 32 and 29 at% of 4He and 3He and were respectively stable up to 573 and 723 K both in vacuum and under inert gas flow. In-situ p-EBS (proton Elastic Back Scattering) allowed monitoring the He release accompanied by blistering/delamination effects visualized by SEM. These results show the potentiality of annealing to hold nano-porous structures after liberation of trapped gas.

This paper presents a recent study on a Roman period marble sculpture depicting Empress Livia and the portraits of Germanicus and Drusus Minor, found at the praesidium of Asido (Medina Sidonia, Cádiz, Spain). The sculptures retain extensive evidence of their original polychromy. The properties and spatial distribution of these pigment remains were investigated by portable non-invasive and micro-destructive techniques, applying digital microscopy, and UV/ VIS/NIR/SWIR spectroscopy, portable XRF and SEM–EDS analysis. The study revealed the presence of Egyptian blue and ochre on Livia’s mantle and charcoal black on Livia’s eyes and hair, remains that were not clearly visible to the naked eye. This is a significant approach, used to identify colours on ancient marble sculpture, which transforms our understanding of these unique pieces. Elemental composition analysis by pXRF has confirmed the evidence of pigments, furthermore supported by the Raman results, making it possible to develop and reconstruct the colour palette that originally brought these sculptures to life in vibrant polychrome. The research offers a new methodology for identifying pigments on marble sculpture and opens new ways for investigating other types of material culture aided by the development of the analytical equipment mentioned.