Anders Lindahl
Professor emeritus
The archaeometry of tuyeres from the Great Zimbabwe and wider implications for its iron production technologies
Författare
Summary, in Swedish
Abstract
Recent research in the wider archaeological landscape of Great Zimbabwe recovered more
evidence of metallurgical tuyeres fused in varied multiples indicative of their use in natural
draft iron smelting technologies. We report the first detailed chemical, microstructural and
thermal analyses of these ceramic materials most likely associated with large-scale iron production at the zenith of the Great Zimbabwe civilization in southern Africa (ca 12th-16th century AD). The bulk chemistry of the studied sample reveals striking dissimilarities in elemental composition between sites. attributable to the adaptation of ceramic technology to local clay materials across the landscape. Only a few sits seem related, suggestive of preference for the same source or a type of clay with a similar soil chemistry, raising questions regarding contestations and negotiations over coveted materials by rival technicians. Highly refractive clays were of great priority to withstand the intense heat and long hours of smelt as proven by the resistance of the studied sample under maximum temperature exposure during analysis. Petrographic analyses reveal that self-tempered clays were most likely selected for this purpose as suggested by the dominance of silt and fine sand in samples. Wherever and whenever such clays were scarce crushed coarse sand and fine gravel were added to the clay to improve the stability and temperature resistance of the tuyeres, given the long hours of smelt and intense heat associated natural draft technologies. Based on these observations, we argue that the sophisticated iron technology of Great Zimbabwe built on by an advanced ceramic technology, revealing the existence of a high degree of engineering ingenuity in the area at some time, apart from its unique and famous drystone architecture.
Recent research in the wider archaeological landscape of Great Zimbabwe recovered more
evidence of metallurgical tuyeres fused in varied multiples indicative of their use in natural
draft iron smelting technologies. We report the first detailed chemical, microstructural and
thermal analyses of these ceramic materials most likely associated with large-scale iron production at the zenith of the Great Zimbabwe civilization in southern Africa (ca 12th-16th century AD). The bulk chemistry of the studied sample reveals striking dissimilarities in elemental composition between sites. attributable to the adaptation of ceramic technology to local clay materials across the landscape. Only a few sits seem related, suggestive of preference for the same source or a type of clay with a similar soil chemistry, raising questions regarding contestations and negotiations over coveted materials by rival technicians. Highly refractive clays were of great priority to withstand the intense heat and long hours of smelt as proven by the resistance of the studied sample under maximum temperature exposure during analysis. Petrographic analyses reveal that self-tempered clays were most likely selected for this purpose as suggested by the dominance of silt and fine sand in samples. Wherever and whenever such clays were scarce crushed coarse sand and fine gravel were added to the clay to improve the stability and temperature resistance of the tuyeres, given the long hours of smelt and intense heat associated natural draft technologies. Based on these observations, we argue that the sophisticated iron technology of Great Zimbabwe built on by an advanced ceramic technology, revealing the existence of a high degree of engineering ingenuity in the area at some time, apart from its unique and famous drystone architecture.
Avdelning/ar
- Kvartärgeologi
Publiceringsår
2017
Språk
Engelska
Sidor
2-30
Publikation/Tidskrift/Serie
Studies in Global Archaeology
Volym
22
Länkar
Dokumenttyp
Working paper
Förlag
tudies in Global Archaeology
Ämne
- Archaeology
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1651-1255
- ISBN: 978-91-506-2591-2