Hunting colours: origin and reuse of glass tesserae from the Wierum terp
Rosa Crocco|Hans Huisman|Yvette Sablerolles|Julian Henderson|Bertil van Os|Annet Nieuwhof
Abstract Mosaic glass tesserae were imported to Dutch sites during the Early Medieval period, probably address demand for coloured needed in ornamental bead manufacture. Although challenging, because of uncertainty material’s context, Wierum collection represents an extraordinary opportunity, being most significant find Netherlands date. The combined use electron microprobe analysis (EMPA) and hand-held X-ray fluorescence spectrometry (HH XRF) allowed us examine other vitreous samples from site. Low levels magnesium potassium oxides (&lt;1.5 wt%) chemical components linked with silica source, fluxes, opacifiers chromophores are compatible older Roman soda-lime-silica production. Alumina calcium oxide contents together adoption antimony-based mosaic a first third century AD tradition. We assume that these collected spoliation lavish building reused objects produced locally. hypothesis seems be confirmed by presence still embedded mortar, stone fragments rounded fragment Egyptian blue.
Archaeological and Anthropological Sciences|University of Groningen research database (University of Groningen / Centre for Information Technology)|University of Groningen research database (University of Groningen / Centre for Information Technology)