6 research outputs found
Vitrified hillforts as anthropogenic analogues for nuclear waste glasses – project planning and initiation
Moving metals III: Possible origins for copper in Bronze Age Denmark based on lead isotopes and geochemistry
This article presents the results of a comprehensive provenance study based on a combined geochemical-isotopic and archaeological approach, comprising 98 analyses of 97 copper-alloy objects from the Danish Bronze Age. When it comes to the question of the origin of the metal, our interpretations diverge somewhat from earlier established theories about the origin of copper imported to Denmark, which mainly pointed to Central and Eastern Europe. Clear geochronological patterns in the Danish dataset are interpreted as being due to shifts in ore sources; reflecting varying areas of origin as well as the utilization of varying ore types. This again relates to shifting trade networks/suppliers and shifting technological trends. Plausible sources for Danish copper-alloys identified in the current study are ore regions in the British Isles, Alpine ore districts in Italy and Austria, as well as
ore regions in the western part of the Mediterranean and to some degree the Slovak Carpathians. The comparison includes hundreds of recently published lead isotope data for ores in Slovakia, the Iberian Peninsula and the Italian and Austrian Alps
A Scandinavian Relief Brooch: Artistic Vision and Practical Method Combined
This is an Accepted Manuscript of an article published by Taylor & Francis in Medieval Archaeology on December 20, 2018, available online: http://www.tandfonline.com/10.1080/00766097.2018.1535384.THIS PAPER considers the craftspeople that created ornamental metalwork, the contexts in which they operated, and the communication they had with their contemporaries. The study focuses on the Dalem brooch, a 6th-century Scandinavian relief brooch from Norway. By examining an object which expresses a complex symbolic language through intricate and demanding crafting processes, we emphasise the importance of considering both ornamentation and technology when studying these exquisite dress items. The brooch was manufactured from a variety of materials and decorated in Salin Style 1. This ornamentation, with its religious, political and social connotations, was completely integrated into the object from its conception. A combination of new and old designs indicates that the craftspeople purposefully created and transformed motifs for use on the brooch, operating within a creative, cross-disciplinary and intellectual centre of expertise.acceptedVersio
Micro- and Nanoscale Surface Analysis of Late Iron Age Glass from Broborg, a Vitrified Swedish Hillfort
Archaeological glasses with prolonged exposure to biogeochemical processes in the environment can be used to understand glass alteration, which is important for the safe disposal of vitrified nuclear waste. Samples of mafic and felsic glasses with different chemistries, formed from melting amphibolitic and granitoid rocks, were obtained from Broborg, a Swedish Iron Age hillfort. Glasses were excavated from the top of the hillfort wall and from the wall interior. A detailed microscopic, spectroscopic, and diffraction study of surficial textures and chemistries were conducted on these glasses. Felsic glass chemistry was uniform, with a smooth surface showing limited chemical alteration (<150 nm), irrespective of the position in the wall. Mafic glass was heterogeneous, with pyroxene, spinel, feldspar, and quartz crystals in the glassy matrix. Mafic glass surfaces in contact with topsoil were rougher than those within the wall and had carbon-rich material consistent with microbial colonization. Limited evidence for chemical or physical alteration of mafic glass was found; the thin melt film that coated all exposed surfaces remained intact, despite exposure to hydraulically unsaturated conditions, topsoil, and associated microbiome for over 1,500 years. This supports the assumption that aluminosilicate nuclear waste glasses will have a high chemical durability in near-surface disposal facilities.</p