Raman Spectroscopy as a Tool for Garnet Analysis and Investigation on Samples from Different Sources

During the Hellenistic period, Garnet was a popular stone for use both as seals and as decorative inlay in jewellery1. The Collectors of garnets and minerals often attach great importance to the provenance or country of origin2. Therefore, “the goal of origin determination” is to provide the geographic provenance of a garnet and can be defined as: the attribution of a stone to a specific type of deposit and the attribution of a stone to a mining area, a geographic locality, or country. In this research work we present the identification and the provenance of 9 garnets from 7 different localities. This is possible because the full range of properties of a garnet measured and observed in the laboratory reflect the specific conditions of its genetic background during the natural crystallization process. We used Raman spectroscopy analysis as a tool which provides even further information to distinguish garnets from different localities. Since each specific member of the isomorphous series shows a characteristic pattern, the Raman Effect can be used as a tool of identification. Our experimental results illustrate this concept.