Raman approach to investigate painted decorations and manufacture technology of fake Greek and Italic pottery: a contribution to authentication

Faking manufacture of ancient pottery is a phenomenon connected to the circulation and trade of unknown archaeological objects, aimed at increasing the earnings of unscrupulous sellers. In this traffic, craftsmen use pseudoscientific skills to produce modern artefact inspired to the ancient ones for fraudulent purposes, mimicking the original materials and ancient manufacturing technologies. In the authentication of decorated ancient pottery, micro-Raman spectroscopy can provide a contribution to the study of constituent materials and manufacturing processes, thanks to the possibility of obtaining data in non-destructive mode or by micrometric samples and to its high sensibility to detect mineralogical and low-crystallinity phases in the decoration. This paper is focused on the characterisation of mineralogical compounds in black glazes and in polychrome overpainted decorations of pseudo-archaeological potteries, which embody different levels of forger's skill, corresponding to an increasing gradualness in the interpretative complexity of the data acquired. For each case study, the specific contribution of micro-Raman spectroscopy to the characterisation of the surface decorations is highlighted, thus providing important clues about the counterfeiters modus operandi and suggesting its possible use as one of the tools for a multi-analytical authentication protocol for this kind of pottery artefacts.