Miljana Radivojević

Tainted ores and the rise of tin bronzes in Eurasia, c . 6500 years ago

The earliest tin bronze artefacts in Eurasia are generally believed to have appeared in the Near East in the early third millennium BC. Here we present tin bronze artefacts that occur far from the Near East, and in a significantly earlier period. Excavations at Pločnik, a Vinča culture site in Serbia, recovered a piece of tin bronze foil from an occupation layer dated to the mid fifth millennium BC. The discovery prompted a reassessment of 14 insufficiently contextualised early tin bronze artefacts from the Balkans. They too were found to derive from the smelting of copper-tin ores. These tin bronzes extend the record of bronze making by c. 1500 years, and challenge the conventional narrative of Eurasian metallurgical development.

Inventing Metallurgy in Western Eurasia: a Look Through the Microscope Lens

The quest for the ‘when’ and ‘where’ of the worlds earliest metallurgy has been dominating scholarly research on this topic for decades. This paper looks beyond the question of origins by discussing ‘how’ and ‘why’ metallurgy was invented. It looks into choices and skills involved in selection, experimentation and processing of distinctively coloured copper minerals and ores throughout c. 2000 years in the Balkans. The body of evidence is built around the currently earliest evidence for copper smelting, dated at c. 5000 bc and discovered in the Serbian Vinca culture site of Belovode. The ‘microstructure’ of a metal invention process is explored through optical and compositional analyses of a selection of copper minerals and metal production evidence: ores, slags, slagged sherds and metal droplets recovered from seven settlements in Serbia and Bosnia and Herzegovina, altogether dated between the late seventh and the late fifth millennia bc. This research suggests an independent technological trajectory of the emergence of metallurgy in the Balkans based on a unique technological meme, black and green mineral, which follows the evolution of early metallurgy from mono- to polymetallic within the fifth millennium bc.

Community structure of copper supply networks in the prehistoric Balkans: An independent evaluation of the archaeological record from the 7th to the 4th millennium BC

The dataset includes trace element analyses for 410 copper-based objects from the Balkans (c. 7th - 4th mill BC), with PCA scores calculated out of log-normalised values, altogether accompanied with relevant archaeological, chronological and geographical data. The article abstract: Complex networks analyses of many physical, biological and social phenomena show remarkable structural regularities, yet, their application in studying human past interaction remains underdeveloped. Here, we present an innovative method for identifying community structures in the archaeological record that allow for independent evaluation of the copper using societies in the Balkans, from c. 6200 to c. 3200 BC. We achieve this by exploring modularity of networked systems of these societies across an estimated 3000 years. We employ chemical data of copper-based objects from 79 archaeological sites as the independent variable for detecting most densely interconnected sets of nodes with a modularity maximization method. Our results reveal three dominant modular structures across the entire period, which exhibit strong spatial and temporal significance. We interpret patterns of copper supply among prehistoric societies as reflective of social relations, which emerge as equally important as physical proximity. Although designed on a variable isolated from any archaeological and spatiotemporal information, our method provides archaeologically and spatiotemporally meaningful results. It produces models of human interaction and cooperation that can be evaluated independently of established archaeological systematics, and can find wide application on any quantitative data from archaeological and historical record.

Photographs of Cu-As-Sn binary and ternary metal pellets as supporting material for the article: "Experimental design of the Cu-As-Sn ternary colour diagram"

The dataset supports the article: Radivojevic, M., Pendic, J., Srejic, A., Korac, M., Davey, C., Benzonelli, A., Martinon-Torres, M., Jovanovic, N., and Kamberovic, Ž. (2017). Experimental design of the Cu-As-Sn ternary colour diagram. Journal of Archaeological Science, https://doi.org/10.1016/j.jas.2017.12.001. Abstract: The aesthetic appearance of metals has long been recognised in archaeometric studies as an important factor driving inventions and innovations in the evolution of metal production. Nevertheless, while the studies of ancient gold metallurgy are well supported by the modern research in colour characteristics of gold alloys, the colour properties of major prehistoric copper alloys, like arsenical copper and tin bronzes, remain either largely understudied or not easily accessible to the western scholarship. A few published studies have already indicated that alloying and heat treatment change the colours of copper alloys, although they are mainly based on the examples of prehistoric tin bronze objects and experimental casts. Here we present the procedure for building the Cu-As-Sn ternary colour diagram, starting with experimental casting of 64 binary and ternary alloys in this system. We used two types of information to produce two different ternary colour diagrams: one, based on photographs of the samples, and the other, established on the colorimetric measurements. Furthermore, we developed the procedure for creating a graphic representation of colours in the Cu-As-Sn ternary diagram using QGIS. As an initial case study, we plotted the composition of the world’s earliest tin bronze artefacts; the graphic representation further supports claims about the importance of golden hue for their invention and demand, c. 6,500 years ago. We argue that the presented colour diagrams will find wide use in future investigations of aesthetics of prehistoric copper alloys.