Combined Scanned Macro X-Ray Fluorescence and Reflectance Spectroscopy Mapping on Corroded Ancient Bronzes

Bronze is an alloy composed primarily of copper and tin and since its discovery is widespread in the whole world. This alloy can thus be found in many archaeological sites and its study can give information about the technology of production, the trading routes, or the warfare within a region. However, bronze artefacts can undergo severe alteration processes, and the formation of corrosion layers of different copper minerals can prevent the readability of the artefact or even destroy it, as in the case of the ‘bronze disease’. Their preservation is crucial for maintaining a connection to our cultural heritage. In this paper, we present the study of some corroded bronze artefacts found in different burying conditions. They have been analysed through a scanner system that combines two non-invasive techniques, macro XRF (MA-XRF) and visible, near infrared, short wave infrared (VIS-NIR-SWIR) reflectance, to unravel information about the metal and the patina composition, thickness, and distribution. As the corrosion of bronze depends on the burying conditions and the alloy composition, these data are of the utmost importance to understanding the alteration processes occurring in the archaeological site and to ensure the artefacts’ optimal preservation

Scientific analyses beyond the excavation: Studies for a non invasive preliminary approach

Domo is an archaeological site located in the Foreste Casentinesi National Park, near the town of Bibbiena, in the province of Arezzo (Tuscany). Since the '80, investigations at Domo have revealed a Roman domus with a Roman baths complex. Unfortunately, the rich stratigraphy was almost completely lost during the first excavations. Since 2008 the archaeological site was reopened by Archeodomani s.a.s., a company that deals with promotion of cultural heritage, and it is still under summer excavation campaigns. In the future perspective to try and solve doubts about the site phase sequence of the Roman baths complex, not easy to understand now for several use modifications of the different areas, we developed an analytical method that could allow a large scale investigation limiting the sampling. In this paper, the preliminary results obtained for mortar are presented, both from the walls and from the binding of cocciopesto of the floor, with XRD (X Ray Diffraction) and ED-XRF (Energy Dispersive X-Ray Fluorescence) analysis on ground samples. XRD analysis was performed at ICVBC-CNR (Milan) and the diffraction data (Cu-Ka, 1.5418 \uc3\u85) were collected on a J-J Panalytical X'Pert PRO diffractometer. Grounded samples were placed in aluminium sample holder or dusted on frosted glass sample holder, depending on sample amount. XRF measurements were performed at Physics Department of Milan University using a portable EDXRF spectrometer (Assing Lithos 3000) exploiting polychromatic radiation from a Mo anode X-ray tube. Both analyses were performed after preliminary observation of the samples by stereo-microscope and the results obtained through XRF and XRD analyses were compared to get more complete information about samples. Data were also submitted to multivariate analysis (Hierarchical Clustering) to get material classification. The comparison between the classification obtained and archaeological interpretation is still in progress; the collection of analytical data will go on in future excavation campaigns. The complete overview will be part of a project to promote the archaeological site through an online portal

Da Veronese a Farinati. Storia, conservazione e diagnostica al Museo di Castelvecchio di Verona

Schedatura di opere del Museo analizzate con le apparecchiature nell'ambito del Master "Dentro l'immagine" 2008-0

An integrated multi-analytical approach to the study of the dome wall paintings by Correggio in Parma cathedral

The restoration of one of the most famous masterpieces of the Renaissance, the wall paintings regarding the Assumption of the Virgin Mary painted inside the dome of the Cathedral of Parma by Antonio Allegri called Correggio (1489-1534) between 1526 and 1530, allowed an in-depth chemical-physical study of materials. Non-invasive infrared imaging and spectroscopic techniques (reflectance spectrometry in the visible range and in-situ X-ray fluorescence) and micro-invasive analytical techniques (optical microscopy, scanning electron microscopy with energy dispersive X-ray microanalysis, powder X-ray diffraction, micro-FTIR spectroscopy, micro-Raman spectroscopy, and gas chromatography coupled with mass spectrometry) were chosen in order to provide the higher set of significant data, limiting as much as possible sampling. The joined use of different techniques allowed to deeply explore Correggio's palette, on the use of a fresco and/or a secco technique, to study as well degradation products and the diffused and old restoration materials like consolidants. The study allowed the characterization of a wide range of pigments, the identification of the binding media, mainly egg and animal glue, the restoration materials (acrylic resins, paraffin waxes, various pigments) and the degradation products (calcium sulfate dihydrate and calcium oxalate). © 2013 Elsevier B.V