Samenvatting
Roman glass is studied here by means of optical absorption spectroscopy, in order to provide an objective method to quantitatively evaluate colour. The dataset is composed of 165 soda-lime silicate glass samples from various western European sites, mainly dated from the first to fourth century AD, and containing variable amounts of iron, manganese and/or antimony. Iron redox ratios and colour coordinates (based on the CIELab colour system) are determined and put in relation with the thickness of samples and their manganese/antimony contents. Results reveal thickness as a crucial parameter when discussing glass hues, thus leading to a differentiation between the ‘intrinsic’ and ‘perceived’ colour of glass objects (i.e. the colour of the object with the thickness normalised to 1 mm, and that with its original thickness, respectively). Apart from HIMT and purple glass, the concentration of ferrous iron appears to be correlated with a* — a colourimetric parameter determining how green the glass is. Significant relations of antimony/manganese contents versus iron redox and glass colour are also considered, resulting in quantitative arguments to entitle antimony-decoloured glass as the most oxidised and colourless glass.
Originele taal-2 | English |
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Artikelnummer | 109 |
Tijdschrift | Archaeological and Anthropological Sciences |
Volume | 12 |
Nummer van het tijdschrift | 6 |
DOI's | |
Status | Published - 13 mei 2020 |
Bibliografische nota
Funding Information:The authors are very grateful to Sofie Vanhoutte from Agentschap Onroerend Erfgoed, Brussels, Belgium, who gave access to the glass from Oudenburg and to Professor Patrick Degryse from Katholieke Universiteit Leuven for kindly making available the glass from the shipwreck of Ouest Embiez 1 he received from DRASSM, France. They would also like to thank Bart Lippens for the glass polishing.
Funding Information:
This research was supported by a PhD fellowship by the Research Foundation – Flanders (Fonds voor Wetenschappelijk Onderzoek, FWO), grant number 11Z8417N. Acknowledgements
Publisher Copyright:
© 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.