Non-destructive spectroscopic investigation of artefacts from middle Hallstatt period—case study of a stone bead from Tărtăria I hoard, Romania.

A stone bead, part of a necklace found in a middle Hallstatt period—type of settlement—the Tărtăria site in Alba County, Romania, was investigated following a non-destructive approach, by means of energy-dispersive X-ray fluorescence spectrometry and Fourier transform infrared spectroscopy. The highly heterogenous object, found together with numerous bronze and iron objects, appeared to be a variety of chalcedony rich in iron and copper impurities, still preserving clay minerals from the sedimentary matrix in some of the areas. Organic molecules found at the surface of the stone artefact may indicate the presence of a wax or resin residue, possible evidence of early craft specialization. The non-destructive protocol applied allowed an in-depth characterization of the artefact, providing important information not only on the crystal structure but also on the diagnostic impurities present within this peculiar stone bead. [ABSTRACT FROM AUTHOR]