A lead-framed glass mirror from a Roman woman's grave in Padua/Patavium (north-eastern Italy) – investigating its function and production with a multidisciplinary approach

• Published in: Journal of cultural heritage Vol. 38; pp. 94 - 105
• Main Authors: Rossi, Cecilia, Pettenò, Elena, Emanuele, Sara, Faresin, Emanuela, Salemi, Giuseppe, Mariotti, Mosè, Molin, Gianmario
• Format: Journal Article
• Language: English
• Published: Elsevier Masson SAS 01.07.2019
• Subjects: 3D scanning; Convex sphere optics; Lead isotope ratios; Restoration methodologies; Sb-colourless glass; Sb-colourless glass; Restoration methodologies; Lead isotope ratios; 3D scanning; Convex sphere optics
• ISSN: 1296-2074; 1778-3674
• DOI: 10.1016/j.culher.2018.11.012

•The convex surface was obtained from a Sb-colourless glass-blown sphere.•The reflective effect was given by a thin lead coat on the concave side.•The lead frame and the glass coating show comparable lead isotope ratios.•Frame type and lead isotope ratios set the production in the Southern Carpathians.•Spherical shape and low surface roughness ensured an excellent view for the makeup. A small Roman mirror, made up of a square lead frame and a convex reflective glass surface, was recently recovered in Padua in a grave dating back to the second half of the 2nd century AD. It was investigated with a multidisciplinary approach. During restoration, the artefact was dismantled, its individual components cleaned, consolidated and then reassembled. Chemical and isotopic analyses were carried out on microscopic fragments from both the glass and the lead components to identify their origin and production technologies. Structured-light 3D scanning was used both to produce a model of the artefact and to reconstruct its optical properties. Archaeometric results show that the 200 μm thick reflective glass surface, coated with a thin lead film, belongs to the Sb-colourless group. The lead frame is now totally oxidised. The lead isotope ratios of both the glass coating and the frame show a common composition, statistically close to some Romanian ores. These data suggest a multistep production process, most likely carried out in the same workshop. The distribution of similar finds mainly between the Northern-Adriatic basin and the Danube could indicate that these products were manufactured in the central-eastern provinces of the Roman Empire, presumably in the Southern Carpathian area, close to the local lead ore deposits. The typology is well defined thanks to the 3D model that is an important tool for morphometric investigations. The optical properties of the mirror, given by its convex spherical surface with a 9 cm radius, suggest the object was actually used as a makeup tool. In conclusion, this multidisciplinary approach reveals that despite its non-precious materials, the mirror can be considered a product of superior technological and scientific skills.