'Any study of Great Zimbabwe has to rely a great deal on re-examining and re-assessing the work of early investigators, the men who removed all the most important finds from the ruins and stripped them of so much of their deposits ' (Garlake 1973: 14

Glass beads have been produced and traded for millennia all over the world for use as everyday items of adornment, ceremonial costumes or objects of barter. The preservation of glass beads is good and large hoards have been found in archaeological sites across the world. The variety of shape, size and colour as well as the composition and production technologies of glass beads led to the motivation to use them as markers of exchange pathways covering the Indian Ocean, Africa, Asia, Middle East, the Mediterranean world, Europe and America and also as chronological milestones. This review addresses the history of glass production, the methodology of identification (morphology, colour, elemental composition, glass nanostructure, colouring and opacifying agents and secondary phases) by means of laboratory based instruments (LA-ICP-MS, SEM-EDS, XRF, NAA, Raman microspectroscopy) as well as the mobile instruments (pXRF, Raman) used to study glass beads excavated from sub-Saharan African sites. Attention is paid to the problems neglected such as the heterogeneity of glass (recycled and locally reprocessed glass). The review addresses the potential information that could be extracted using advanced portable methods of analysis.

Much is known about the economy and spatial organization of Zimbabwe culture entities of Mapungubwe, Great Zimbabwe and Khami but less in terms of their origins and relationship with each other. Based on little tangible evidence, it is believed and widely accepted that the societies based at Mapungubwe (AD 1220-1290), Great Zimbabwe (AD 1300-1450) and Khami (AD 1450-1820) rose, developed and eclipsed in tandem. A recent reexamination of the relationship between these settlements and related ones using local ceramics, imported artefacts, stone architecture and Bayesian modelling suggests this may not have been the case. The synthesis proffered revelations which temper the widely accepted assumption that sociopolitical complexity in southern Africa began in the Shashi-Limpopo Valley before anywhere else in the region. Firstly, there are numerous Zhizo and Leopard's Kopje sites that predate Mapungubwe but contain prestige goods and stone structures dating from the late first millennium AD. Secondly, material culture studies and modelled radiocarbon dates indicate that Great Zimbabwe evolved out of Gumanye while Khami, like Mapungubwe, may have developed out of the Leopard's Kopje. In fact, Great Zimbabwe was already a place of importance when Mapungubwe collapsed. Thirdly, Khami and Great Zimbabwe overlapped for over a century, before the latter buckled. Therefore, the evolution of sociopolitical complexity in southern Africa may have followed trajectories that are different from what the current understanding implies. (1450-1820 ap. J-C) auraient été fondés, se seraient développés et se seraient effondrés successivement. De récentes recherches ont exploré les relations entre ces différents sites ainsi que ceux qui y sont rattachés, en étudiant les céramiques locales, les objets importés, la typologie des murs de pierres et notamment les préférences résidentielles, et la modélisation Bayesienne. La synthèse permet de tempérer la vision dominante selon laquelle la complexité sociopolitique dans le Sud de l'Afrique a commencé dans la vallée du Shashi-Limpopo, avant tout autre site dans la région. Tout d'abord, il y a de nombreux sites antérieurs à Mapungubwe, Zhizo et Leopard's Kopje, avec des biens de prestige et des fortifications en pierre datant de la fin du premier millénaire ap. J-C. Ces caractéristiques seraient apparus à K2 et Mapungubwe dans la dépression du Limpopo. Deuxièmement, la culture matérielle et les datations carbones indiquent que Great Zimbabwe était déjà un lieu important quand Mapungubwe s'est effondré. Enfin, Khami et Great Zimbabwe coexistent pendant plus d'un siècle, avant que ce dernier ne tombe en déchéance. Par conséquent, la complexité sociopolitique dans le Sud de l'Afrique a probablement emprunté des trajectoires différentes de celles qui sont actuellement tracées avec les connaissances disponibles.

Across the globe, the emergence of complex societies excites intense academic debate in archaeology and allied disciplines. Not surprisingly, in southern Africa the traditional assumption that the evolution of socio-political complexity began with ideological transformations from K2 to Mapungubwe between CE1200 and 1220 is clouded in controversy. It is believed that the K2−Mapungubwe transitions crystallised class distinction and sacred leadership, thought to be the key elements of the Zimbabwe culture on Mapungubwe Hill long before they emerged anywhere else. From Mapungubwe (CE1220–1290), the Zimbabwe culture was expressed at Great Zimbabwe (CE1300–1450) and eventually Khami (CE1450–1820). However, new fieldwork at Mapela Hill, when coupled with a Bayesian chronology, offers tremendous fresh insights which refute this orthodoxy. Firstly, Mapela possesses enormous prestige stone-walled terraces whose initial construction date from the 11th century CE, almost two hundred years earlier than Mapungubwe. Secondly, the basal levels of the Mapela terraces and hilltop contain élite solid dhaka (adobe) floors associated with K2 pottery and glass beads. Thirdly, with a hilltop and flat area occupation since the 11th century CE, Mapela exhibits evidence of class distinction and sacred leadership earlier than K2 and Mapungubwe, the supposed propagators of the Zimbabwe culture. Fourthly, Mapungubwe material culture only appeared later in the Mapela sequence and therefore post-dates the earliest appearance of stone walling and dhaka floors at the site. Since stone walls, dhaka floors and class distinction are the essence of the Zimbabwe culture, their earlier appearance at Mapela suggests that Mapungubwe can no longer be regarded as the sole cradle of the Zimbabwe culture. This demands not just fresh ways of accounting for the rise of socio-political complexity in southern Africa, but also significant adjustments to existing models.

In southern African Iron Age studies, there are few attempts to systematically apply and include laboratory analyses when studying archaeological ceramic materials. As demonstrated in this paper, such analyses help to understand the technological aspects such as raw materials, manufacturing techniques and vessel function. Combined with vessel shape and decoration as well as ethnographic studies, the results provide new ways to understand local and regional distribution networks of the ceramics craft. Furthermore, laboratory analyses are most useful when studying continuity and changes in the ceramics handicraft over time, which has implications both on cultural and social change as seen in the shift in ceramic production techniques. We use examples from Zimbabwe and South Africa to illustrate these changes and discuss them in a broader social and technological context in Iron Age southern Africa.