Combined spectroscopic analysis of stratified glass eye beads from China dated to the Warring States Period

We herein report the application of a combined spectroscopic approach for the analysis of eight stratified glass eye beads unearthed from China, which was dated back to the Warring States Period (475 bc to 221 bc). Portable X‐ray fluorescence spectrometry (pXRF) was used to determine that seven samples were typical natron type soda–lime–silicate glass beads with low contents of MgO and K2O except for one plant‐ash type soda–lime–silicate sample. In addition, combined with micro‐Raman spectroscopy, two different types of colorants were present in these beads, namely oxidized transition metals such as Co, Cu and Fe, and antimony‐based compound opacifiers/colorants. Furthermore, the distribution of their glassy and scattering phases could be determined by the optical coherence tomography (OCT) images, in which it exhibits that their morphologies were related to their Sb contents. According to the determined typology, chemical composition, micro‐crystal, and eyeball structural characteristics within the samples, the possible relations among them were speculated. It is the most interesting finding that seven natron type soda–lime glasses could be imported from the eastern Mediterranean area and one plant‐ash type glass could be imported from the eastern region of the Euphrates River such as Iran area. Finally, through comparison with similar contemporary beads excavated from the famous tomb of Marquis Yi of the Zeng State (~433 bc) in the Hubei Province, provenance studies of these beads were carried out, and their origins and relationships are discussed briefly. Copyright © 2017 John Wiley & Sons, Ltd.