A glass workshop in 'Aqir, Israel and a new type of compositional contamination. (February 2021)

• Record Type: Journal Article
• Authors: Chen, Chen; Freestone, Ian C.; Gorin-Rosen, Yael; Quinn, Patrick S.
• Is Part Of: Journal of archaeological science. Volume 35(2021)
• Publication Date: 2021-02
• Subjects: The Levant -- Byzantine -- Glass-working -- Glass furnace -- Technology -- SEM-EDS -- Thin-section petrography -- Provenance; Archaeology -- Periodicals; Archaeology -- Research -- Periodicals; 930.1
• DOI: 10.1016/j.jasrep.2020.102786
• Languages: English
• ISSNs: 2352-409X

Abstract

Highlights: First detailed investigation of the furnace materials of a secondary glass workshop from Israel. Apollonia type glass melted in a brick built furnace at around 1100 °C. Lime-rich materials may represent lining of furnace tank with a release agent. Glass from furnace shows a previously unrecognised contamination with strongly correlated Fe2O3 and CaO. Similar contamination can be recognised in Byzantine vessel glass assemblages on Cyprus. Abstract: Materials associated with a secondary workshop of early Byzantine date (4th-5th centuries) were unearthed in excavations by the Israel Antiquities Authority in 'Aqir, central Israel. Fragments of furnace structure, production debris and glass vessels have been analysed by scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDS) and thin-section petrography. The results suggest that the workshop melted raw glass chunks of similar composition to the primary glass made at Apollonia, Israel, to produce secondary glass products. Some glass vessels associated with the furnace are of different composition, and some of these may represent material brought in as cullet for recycling. The furnace was built with ceramic bricks comprising alluvial-type clay with inclusions of quartz sand, probably added as temper. It was fired by potash-rich fuel to approximately 1100 °C. Lime mortar was used either to cement the gaps between mudbricks or to line the furnace as a parting layer, and it has introduced a previously unrecognised type of contamination in glass of the period, mainly of Fe2 O3 and CaO. The contamination may be identified in glass vessel assemblages elsewhere but is not ubiquitous. As its origin relates to the furnace structure, its occurrence may depend upon chronology or geography and further work is needed to resolve this issue.