We thank the four commentators for adding new dimensions and important data relevant to interpreting the new Ingombe Ilede dates. These contribute to the recent wave of reassessments and critiques of earlier interpretations and frameworks for the development of trade and complexity in southern Africa. Such reconsiderations are made possible by more sophisticated and precise radiocarbon dating, expanded investigation of both new and previously excavated sites, and by the use of chemical analyses to identify differently sourced groups of glass beads and metals (e.g. Pikirayi Reference Pikirayi2009; Robertshaw et al. Reference Robertshaw, Wood, Melchiorre, Popelka-Filcoff and Glascock2010; Chirikure et al. Reference Chirikure, Pollard, Manyanga and Bandama2013, Reference Chirikure, Manyanga, Pollard, Bandama, Mahachi and Pikirayi2014, Reference Chirikure, Bandama, House, Moffett, Mukwende and Pollard2016; Koleini et al. Reference Koleini, Prinsloo, Biemond, Colomban, Ngo, Boeyens and Van der Ryst2016).
The new data provided by Robertshaw and Wood (above) regarding glass bead groups present in several of the burials are particularly valuable, and provide a serendipitous response to Pikirayi's (above) call for chemical analysis of the Ingombe Ilede beads. The data show that beads of the soda-alumina Khami group, which were produced in India and traded primarily between the mid fifteenth and mid seventeenth centuries, were present in four of the central burials and two of the southern burials. This proves for the first time that both cemetery areas were largely contemporaneous. The presence in four of the central burials of glass beads that align chemically with the earlier plant-ash Zimbabwe bead group is intriguing. Perhaps these two bead groups are not as temporally discrete and non-overlapping as originally proposed. But Robertshaw and Wood elaborate on the possibility, initially raised by du Toit (Reference du Toit1965), that some glass beads were kept as heirlooms. This parallels Oddy's (Reference Oddy1984: 77) observation that some of the gold beads in the Ingombe Ilede burials were extremely worn and looked “as though they were rather old when buried”. This is a reminder that valuable or spiritually charged items may be curated, used and passed along for generations. Chronological designations more precise than ‘terminus post quem’, based on the presence of exotics, require independent corroborating evidence. Certain types of beads and ritually powerful objects, such as the iron gongs of possible Central African manufacture, may have moved along various and indirect routes over a considerable period of time. In the case of the Zimbabwe-series glass beads at Ingombe Ilede, the melting and re-working of beads into novel shapes was apparently involved.
The chronological disjunction between Great Zimbabwe's primary period of involvement in long-distance trade (thirteenth to early fifteenth centuries), and that evidenced by the Ingombe Ilede burials, is underscored by the different forms of copper-cross ingots at the two sites. Our original text made this point, and it was usefully elaborated on by Killick (above). The flanged copper crosses of HXR type were produced in north-western Zimbabwe only after AD 1400. Three of the four richest burials at Ingombe Ilede (burials 1, 2 and 8) contained one or more HXR ingots, as did burial 6. When considered together with the new sixteenth-century dates for burials 3 and 8, nearly all the evidence for greatly expanded trade contacts and social differentiation at Ingombe Ilede dates to the later fifteenth century, at the earliest. Outside of the central cemetery, the midden deposits from both the early (later first millennium AD) and later component produced only very small amounts of copper and a few glass beads (Fagan et al. Reference Fagan, Phillipson and Daniels1969; Phillipson & Fagan Reference Phillipson and Fagan1969). The new dating largely obviates arguments for a marked increase in the scale of pre-Portuguese trade reaching the middle Zambezi. As de Luna notes (above), the case for Ingombe Ilede as a causal factor in shifting trade patterns before 1450, whether to the south with Great Zimbabwe, along the Zambezi or to the west, has collapsed.
De Luna appropriately suggests that research should now investigate the participation of Ingombe Ilede in specific sixteenth-century networks, using chemical or isotopic analysis to identify the pathways along which objects from different source areas moved. Killick (above) points to the potential for sourcing the copper and bronze in the burials using lead isotope analysis. This can successfully differentiate copper from ore sources in the Zambian-DRC Copperbelt, the Zambezi belt around Lusaka, and Hurungwe. Beyond indigenous copper sources, the extraordinary volume of European copper that was shipped to Africa is illustrated by Killick's mention of the 20 tonnes of copper ingots recovered from the 1533 Bom Jesus shipwreck. While lead isotope ratios for the Slovakian copper ingots on the Bom Jesus overlap ratios for the Zambian Copperbelt, as Killick notes, trace element analysis has the potential to differentiate these sources. The gold beads, too, may provide evidence for shifting source areas, if analysed as part of a systematic programme involving beads from key sites, such as Great Zimbabwe, Mapungubwe and Khami.
The re-dating of the Ingombe Ilede burials contributes to the reassessment of earlier scholarship and interpretive narratives concerning second-millennium history in southern Africa. Vibrant field and laboratory programmes are re-examining well-known sites, and providing revised chronological sequences supported by material culture studies. The move away from a primary concern with stone-built wall sequences in Zimbabwe and northern South Africa has produced new types of data that challenge earlier models of trade and evolving socio-political complexity (Chirikure & Pikirayi Reference Chirikure and Pikirayi2008). The idea of Great Zimbabwe as a highly centralised ‘superstate’ that exerted control over trade and production within a large area is challenged by new data that indicate contemporaneous occupation of several other trading centres in a landscape of competing polities (Chirikure et al. Reference Chirikure, Bandama, House, Moffett, Mukwende and Pollard2016). The dynamism and struggle for competitive advantage that Portuguese sources describe for the Mwene Mutapa confederacy after AD 1500 now seem potentially and unexpectedly relevant to understanding these earlier polities. As de Luna notes, Ingombe Ilede is not mentioned in these sources and seems to have been unknown to the Portuguese—in contrast to the Hurangwe copper-producing district. Her assessment of the questions raised by the new dates, and of the need for renewed archaeological research north of the Zambezi, is thoughtful and compelling.
