Archaeometric studies bymeans of complementary and non-destructive physical methodologies with micrometric resolution

Abstract

The approach to the study of cultural heritage and archaeology find is highly interdisciplinary. The archaeometry expert has to be a multidisciplinary figure with different skills in hard sciences (physical, chemical, biological, earth sciences and engineering), humanities (art historians, philologists, curators) and technical disciplines (restorers and conservators). Today the archaeometry expert needs a palette of non-destructive and non-invasive techniques, to improve the understanding of the manufacture, the evolution and/or degradation during the time of the archaeological find. The aims of this thesis is to display the result of archaeometric studies performed in my PhD research, and describe the non-destructive physical methodology and the approaches used to address archaeological questions and problems. The X-ray μCT experimental apparatus implemented at the STAR-Lab facility realized under the PON MaTeRia project, at the University of Calabria (Italy), give us a possibility to acquire several images useful to inspecting the internal morphology of an object. It is a non-destructive diagnostic method used to characterize material microstructure in three dimensions with resolution of the order of micrometer. Artax 400 is a portable μXRF developed by Bruker for archaeometric studies. μXRF is an analytical technique for elemental characterization that provides both qualitative and quantitative information. It’s a non-destructive method which does not require a specific sample preparation, and it allows to carry out investigations in situ. These complementary and non-destructive physical methodologies were used and implemented for the investigation of different archaeological finds from different archaeological contexts. In particular, five case studies are described below: 1. The aim of this case study is to determine the materials, the production process and the technological features of three silver plated coins (two Roman denarii and one Greek statere) preserved in the “Brettii and Enotri” museum in Cosenza. 2. The aim of this case study is to understand the oxidation processes, to know the constituent material and to find hidden signs or inscriptions of two completely oxidated coins preserved in the “Brettii and Enotri” museum in Cosenza. 3. The aim of the current case study is to determine the materials and technological features of a unicum object and to read possible inscriptions and decorations under the superficial encrustations of a bronze plaque. Both archaeological finds have been excavated in the archaeological site of Timpone della Motta, in Francavilla Marittima (CS). 4. In this case study the chemical composition of the bronze alloy and physical technical characteristics of two bronze anthropomorphic couples as pendants (dating to the Early Iron Age) have been studied. The first, called “type B”, were discovered in the archaeological site of Pietrapaola (CS), however the second, called “type A”, . were discovered in archaeological site of Bucita-Rossano (CS). 5. The aim of this case study is to investigate the conservation status and the chemical composition of 12 Magno-Greek bronze mirrors. These prestige goods are a clear example of the high level reached by the handicraft of Magna Graecia. They are preserved in the National Archaeological Museum of Locri Epizephyrii. They were discovered in the grave of the Contrada Lucifero Necropolis and they are dated between the second half of the VI century b.C. and the first half of the IV century b.C.