Multi-analytical approach and microstructural characterisation of glasses from the Celtic oppidum of Třísov, Czech Republic, second to first centuries BC

Abstract

The Late Iron Age–La Tène period in Europe outside the Hellenistic world is characterised by specific glass products in the third to first centuries BC. Evidence of glass-working together with large collections of products (bracelets, ring-beads and other beads) have been reported from several central settlements (e.g. Němčice and Staré Hradisko in Moravia, Manching in Bavaria). These products were made from soda–lime natron-based glass. Raw glass was imported from the Mediterranean and used in local workshops to make personal ornaments. This paper presents a collection of the second- to first-century BC glass from the Celtic oppidum of Třísov in southern Bohemia, Czech Republic. Its archaeology and chemistry were studied in the context of contemporary glass-making and glass-working. The methods of scanning electron microscopy with energy-dispersive spectrometry and laser-ablation–induced coupled plasma–mass spectrometry were used for this purpose. All analysed samples of La Tène glass were found to be made of natron-based glass, comparable with glass produced in the Syro-Palestinian area. For the first time, different layers of body glass and inclusions were separately analysed in ring-beads. In yellow and also white opaque glasses, tin-based opacifiers and colourants were used. Besides typical La Tène ornaments made of natron-based glass, the analysed collection also contains three fragments of vessel made of much later wood-ash glass. As no evidence of glass-working is available from the Třísov oppidum, it is assumed that it functioned as a trading post or a distribution centre for glass products manufactured, e.g. at the Stradonice or Manching oppida. In this respect, the study provides new data on the production and distribution of La Tène glass in central Europe.