Circulation Patterns of Copper-Based Alloys in the Late Iron Age Oppidum of Třísov in Central Europe

Abstract

This article presents an insight into the sourcing and circulation of copper alloys during the Late La Tène period in Central Europe  where the specialised production of metals is regarded as complex and conducted chiefly within the bounds of the oppida. Contrary to the logical, though not necessarily data-based, assumption that local raw materials for the production of bronze were mostly used from the local primary deposits, we argue that an advanced and complex economy of Late Iron Age allowed for the steady and consistent material supply even from distant areas and that such pattern was possibly commonly practised by the oppida sites.  Concurrently, we do not argue against the possibility of the exploitation and processing of the locally mined metal, we only point out that in provenance studies the evidence for that is yet difficult to find. We back our hypothesis by archaeometric analysis of the  assemblage of bronze objects from the oppidum of Třísov (Czech Republic) collected during the long-term investigations of this site. The selection of objects for analyses covers the spectrum from the local products to potentially imported items. A provenance
study based on the analysis of lead isotopes and chemical composition has shown rather homogeneous pattern of lead isotopic values and, on the contrary, quite a variability among the chemical composition of the individual artefact groups suggesting thus 1)  standardised technological procedures for individual types of objects, 2) common recycling of the materials used and/or 3)  contamination of low-leaded alloys from highly leaded bronzes.