A theatrical double-faced mask preserved at the Museum of Lipari (Messina): study and 3D reconstruction through portable equipment

The new tools for 3D survey and modelling (as portable scanners and software packages), often in combination with diagnostics, are nowadays able to provide indispensable elements for the study of archaeological artefacts; their applications to museum’s heritage can be also useful to integrate the traditional graphic documentation and contribute to enhancement and dissemination. This paper shows the benefit of using the aforementioned tools to study the peculiar clay mask No. 11114-E, discovered in 1973 in the Greek necropolis of Lipára, inside tomb No. 1558. The specimen, now exhibited in the Classical Section of the Aeolian Museum, is considered unique both in the Aeolian Islands and in the ancient Greek world, as it is the only one merging two half faces attributable to different characters. This feature, unknown at the time of discovery, has been highlighted in 2018, thanks to a restoration intervention by which a hard concretion layer covering a large portion of the mask surface was removed, bringing to light a smiling young half-face next to an old one with Silenic features. In 2019, the mask was surveyed in situ through a portable and performing laser-scanner arm (the QuantumTM FaroArm by FARO) to produce a high-resolution 3D model useful to enhance the reading of the two halves (not evident enough, due to its state of preservation). The data processing was performed using the Geomagic Wrap software, able to align and merge multiple scans into a single model and to export results in multiple formats, easily shareable and viewable in free software or via the web. Finally, thanks to this method, the successful generation of a digital replica was performed; the resulting replica is useful for dissemination and as a support for the hypothetical reconstruction of the two prototypes taken as models by the craftsman who created the mask.Highlights:A 'mobile laboratory’ consisting of portable equipment has been set up to perform 3D metric surveys on a selection of artefacts preserved at the Museum of Lipari.By means of an ultra-precision laser-scanner arm, a 3D survey on a miniaturistic double-faced mask, belonging to the classical theatrical terracotta, has been performed.A geometrically accurate and realistic 3D final model has been created. This helped the study and reconstruction of the two characters composing the mask.