Dieter Brems

The Sr–Nd isolation procedure for subsequent isotopic analysis using multi-collector ICP-mass spectrometry in the context of provenance studies on archaeological glass

Sr and Nd isotopic analysis of glass can be relied upon to unravel the provenance of the flux component and the sand used in the manufacturing of archaeological glasses, respectively. For a reliable isotopic analysis of the target elements using multi-collector ICP-mass spectrometry, the target elements need to be isolated from the matrix to permit adequate correction for instrumental mass discrimination. In this paper, a simple, fast and reliable analytical method for the isolation of Sr and Nd from complex sample matrixes such as archaeological glasses is proposed. Special attention is focused on the Nd isolation protocol, with the definition of TRU-Spec and Ln-Spec resin bed volumes and of an appropriate HCl concentration to optimize Nd elution from the column.

Geochemical heterogeneity of sand deposits and its implications for the provenance determination of Roman glass

Abstract During the production of natron glass most features of the raw materials are lost and only some bulk geochemical characteristics have potential as provenance indicators. To determine the primary origin of archaeological glass artefacts, suitable sand raw materials have to be accurately characterised. In this respect, information about the possible variation in geochemical properties within a silica source is also vital to account for potential (partial) overlap of different sources. In this study, it is shown that the variation in major and minor elemental composition of beach sand on a local scale is smaller than the variation in Roman natron glass. Therefore, a single sand deposit can be seen as a relatively homogeneous source of silica for glass production. Nd isotopic signatures are identical for all samples analysed. The isotopic composition of Sr however varies considerably due to local variations in the relative proportions of carbonates and silicates (mostly feldspar).