Periodic Reporting for period 1 - METALS (Metallurgical Traditions in West Africa: Technology, Production, and Exchange of Iron and Copper in Nigeria from 700 BC to AD 1800)
Reporting period: 2022-09-01 to 2024-08-31
The METALS project has been terminated early because the Fellow successfully applied for a longer-term position elsewhere which is highly relevant for his personal career development. Therefore, no further updates of this Summary will take place. The project considered two questions as central to this research: 1) what was the evolution of metallurgical traditions in early Nigeria in relation to technical processes and development and raw material choices? 2) how did prehistoric craftspeople in Nigeria interact with the wider region in terms of production, trade and consumption of copper and its alloys through the social network system? Within a short two-year project, original research only for one of the two main metals (iron and copper) can be done. METALS prioritises copper metallurgy as the more elusive technology, but will consider the literature and archaeological evidence for iron metallurgy equally alongside the copper research, not least to lay the foundation for a follow-on project proposal targeting Nigeria’s early iron metallurgy. Therefore, the overall objectives include systematically researching production places for copper and iron, and investigating those for copper through fieldwork. The research successfully identified production remains for copper alloy production, and sampled previously un-analysed copper objects for chemical analysis. The project characterised the composition of metal production related materials (mostly slags and crucibles used to work metal) to reconstruct ancient technological and production processes. Following sampling and chemically analysing bronze objects in collections and museums in West Africa, the project compares the new compositional and lead isotope data from the fieldwork to recently emerging similar data from other parts of Africa, and establishing the chaîne opératoire (sequence of production chain) for copper alloy materials.
During the project, several activities relating to the objectives were performed, including:
Professional training
The fellow received structured ‘learning through research’ training in optical microscopy, pXRF, and Scanning Electron Microscopy working on African materials in the lab, particularly, copper alloy casting moulds and crucibles from Morocco and Ghana, metal objects from Mali and iron slags from Nigeria. He now has expertise beyond the intermediate level to handle these types of equipment for analytical purposes and understand how they can produce data for answering research questions. In line with professional development, the fellow also made a trip to the University of Arizona in the archaeological science Lab of Professor David Killick, where he acquired expertise in identifying copper-related materials in archaeological and geological contexts.
Fieldwork/Museum visits
Direct fieldwork and visits to museums in West Africa were used to acquire the needed materials for the project. The fellow conducted fieldwork at Ile-Ife in Nigeria and excavated an iron smelting site. He visited the Natural History Museum of the Obafemi Awolowo University, Ile-Ife, Nigeria, where many archaeological materials from early works in the city are stored. Samples of iron slag and tuyère used in smelting and smithing, fired clay from the furnace ruins, and ceramics were brought to STARC for analysis. He also surveyed a mine in eastern Nigeria where geological samples were collected. The mine has been proposed as one of the sources of the 9th – 12th century bronze objects from eastern Nigeria. The sample will be processed to be included in the database for comparison to understand sources of archaeological copper-related materials. The fellow also visited the University of Ghana’s Department of Archaeology and Heritage Studies Museum and the Ghana National Museum. Samples of possible brass crucibles and copper-related objects were selected from assemblages from archaeological sites in Ghana. The samples were brought to STARC for analysis. Samples of copper objects from Gao – a medieval urban site in Mali, were also brought to STARC for the study. In addition to the analysis done at the STARC facility, selected samples of the copper objects from Mali were sent to Leuven for Lead Isotope analysis – the technique that helps to identify the source of the metal. All relevant formal export licenses were obtained and deposited at STARC.
Dissemination
The results of the analysis are being prepared for publication. Two assemblages are currently in the manuscript stage. We will continue working on these and ensure that they are published as soon as possible. Preliminary results of the iron metallurgy tradition at Ile-Ife were presented at the World of Iron Conference 2023 in Nairobi, Kenya. A version of the results is to be presented at forthcoming two conferences: The Society of the History of Technology (SHOT) Conference, in July 2024; and the Lagos Studies Association (LSA) 2024 annual conference, in June 2024.
Professional training
The fellow received structured ‘learning through research’ training in optical microscopy, pXRF, and Scanning Electron Microscopy working on African materials in the lab, particularly, copper alloy casting moulds and crucibles from Morocco and Ghana, metal objects from Mali and iron slags from Nigeria. He now has expertise beyond the intermediate level to handle these types of equipment for analytical purposes and understand how they can produce data for answering research questions. In line with professional development, the fellow also made a trip to the University of Arizona in the archaeological science Lab of Professor David Killick, where he acquired expertise in identifying copper-related materials in archaeological and geological contexts.
Fieldwork/Museum visits
Direct fieldwork and visits to museums in West Africa were used to acquire the needed materials for the project. The fellow conducted fieldwork at Ile-Ife in Nigeria and excavated an iron smelting site. He visited the Natural History Museum of the Obafemi Awolowo University, Ile-Ife, Nigeria, where many archaeological materials from early works in the city are stored. Samples of iron slag and tuyère used in smelting and smithing, fired clay from the furnace ruins, and ceramics were brought to STARC for analysis. He also surveyed a mine in eastern Nigeria where geological samples were collected. The mine has been proposed as one of the sources of the 9th – 12th century bronze objects from eastern Nigeria. The sample will be processed to be included in the database for comparison to understand sources of archaeological copper-related materials. The fellow also visited the University of Ghana’s Department of Archaeology and Heritage Studies Museum and the Ghana National Museum. Samples of possible brass crucibles and copper-related objects were selected from assemblages from archaeological sites in Ghana. The samples were brought to STARC for analysis. Samples of copper objects from Gao – a medieval urban site in Mali, were also brought to STARC for the study. In addition to the analysis done at the STARC facility, selected samples of the copper objects from Mali were sent to Leuven for Lead Isotope analysis – the technique that helps to identify the source of the metal. All relevant formal export licenses were obtained and deposited at STARC.
Dissemination
The results of the analysis are being prepared for publication. Two assemblages are currently in the manuscript stage. We will continue working on these and ensure that they are published as soon as possible. Preliminary results of the iron metallurgy tradition at Ile-Ife were presented at the World of Iron Conference 2023 in Nairobi, Kenya. A version of the results is to be presented at forthcoming two conferences: The Society of the History of Technology (SHOT) Conference, in July 2024; and the Lagos Studies Association (LSA) 2024 annual conference, in June 2024.
The identification of archaeological remains of brass working, and potentially brass making, from Ghana was unexpected, and adds considerably to the evidence for brass technology globally. We expect to complete at least two manuscripts and publish them after the end of the project. Our established professional relationships with colleagues and institutions in Ghana, Mali, and Leuven will continue beyond the project. This relationship, especially with West African colleagues will further enhance and encourage the development of archaeological science on the sub-continent.