AV 69, 2018: Timotej KNIFIC, Žiga ŠMIT

ARHEOLOŠKI VESTNIK

ARHEOLOŠKI VESTNIK 69, 2018

Timotej KNIFIC, Žiga ŠMIT

Early medieval glass in Slovenia: Analytical study and beads of plant-ash glass

Abstract

A combined method of proton-induced X-ray and gamma-ray emission (PIXE, PIGE) was used to analyse glass beads and other glass fragments from early medieval sites in Slovenia. An analysis of 179 samples from 25 sites has identified two types of glass: natron and plant-ash glass. They differ according to the alkalis used in their production, which was either natron (a mixture of sodium carbonate and bicarbonate) or the ash of halophytes (coastal plants that tolerate high salinity). Natron glass was manufactured in line with the Roman tradition, while the plant-ash (halophytic) glass is of Eastern origins and started appearing at early medieval sites in Europe in the second half of the 8th c. In Slovenia, plant-ash glass has been identified at 18 sites; it was used in mosaic, segmented, and simple beads, the appearance of which is a significant fact for dating archaeological finds, particularly jewellery from an early period of the Early Middle Ages. The presence of the plant-ash glass beads shifts the suggested early dating for some of the graves with such jewellery to the second half of the 8th and the 9th c. Beads of plant-ash glass are common in graves containing pottery pots, and individual beads of plant-ash glass are also known from hill-top sites and lowland settlements. The most recent beads made of plant-ash glass have been found with the jewellery of the so-called Bijelo Brdo culture (the second half of the 10th and the first half of the 11th c.).

Keywords: Slovenia, Early Middle Ages, PIXE-PIGE analysis, natron glass, plant-ash glass, glass beads, jewellery, equestrian equipment, pottery

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