https://doi.org/10.1140/epjp/s13360-023-04222-8
Regular Article
In situ LIBS-XRF analysis as a combined approach to disclose the production technology of unique wall mirrors from Pompeii
1
Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080, Bilbao, Spain
2
Department of Condensed Matter Physics, Crystallography and Mineralogy, University of Valladolid (UVa), Valladolid, Spain
3
Archaeological Park of Pompeii, Via Villa Dei Misteri 2, 80045, Pompei Scavi, Pompei, Italy
4
Unesco Chair of Cultural Landscapes and Heritage, University of the Basque Country (UPV/EHU), Vitoria-Gasteiz, Spain
Received:
17
October
2022
Accepted:
22
June
2023
Published online:
13
July
2023
It is assumed that the unique wall mirrors found at the Archaeological Park of Pompeii (PAP) are made of obsidian. To contribute to the knowledge of those archaeological artefacts, this work proposes in situ elemental analyses in collaboration with PAP seeking to determine, in a total no-destructive way, the composition and provenance of the main mirror preserved at the House of Gilded Cupids. Comparing the geochemical composition of this black glass with that of obsidian samples collected from the main Mediterranean sources, both X-ray fluorescence (XRF) and laser-induced breakdown spectroscopy (LIBS) confirmed an incompatible content of many key elements. LIBS in-depth analysis excluded the potential relation between the higher concentration of Ca and Mg and the presence of alteration products. In addition, XRF analysis missed the detection of Rb, Y, Zr and Nb, which are widely recognized as the elemental fingerprints of obsidian sources. Combined with the detection of a high content of strontium (500–700 ppm), the in situ elemental data proved that, rather than made of obsidian, the analysed mirror was handcrafted by the fusion of coastal sand. Waiting to extend this study to the other mirrors found at Pompeii, the results here presented indicate the history of these unique artefacts needs to be rewritten.
© The Author(s) 2023
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.