Unearthing Europe’s Bronze Age mining heritage with tin isotopes: a case study from Central Europe W. Powell1*, R. Mathur2, J. John3, M. Price4, H.A. Bankoff5, M. Tisucká6, L. Godfrey7
Being exclusively placer-based, evidence of prehistoric tin mining in Europe was erased rapidly in the fluvial environment. Circumstantial evidence has suggested that the tin ores of the Erzgebirge along the GermanCzech border were exploited in the Bronze Age. To investigate this further, tin ores from the three Erzgebirge plutons, as well as Cornwall, were isotopically characterized and compared with the Sn isotopic composition of Bronze Age tin-bearing artifacts from the region. After accounting for isotopic fractionation associated with the smelting process, a probabilistic approach indicates that at the transition to the Middle Bronze Age, the predominant mining center was the Central Pluton, but mining activity shifted to the Western Pluton for the remainder of the Bronze Age.
Etant exclusivement d’origine alluvionnaire, l’évidence d’exploitation minière d’étain en Europe fut rapidement effacée dans un contexte environnemental fluvial. Une preuve circonstancielle a suggéré que les mines d’étain de l’Erzgebirge, le long de la frontière germano-tchèque, furent exploitées pendant l’Age de Bronze. Une investigation plus poussée dévoile que les mines d’étain des trois massifs plutoniques de l’Erzgebirge, de même que celles de Cornouailles furent caractérisées du point de vue isotopique et comparées – composition isotopique de l’étain - avec les artefacts à étain de l’Age de Bronze de la région. D’après les données de la fracturation isotopique associée à un processus de fusion, une approche à l’aide de probabilités indique qu’au moment de la transition vers l’Age de Bronze, le cœur de l’exploitation minière correspondait au massif plutonique central mais les activités minières se déplacèrent ensuite pour occuper le Massif ouest, durant la période restante de l’Age de Bronze.
Al estar exclusivamente basado en sitios puntuales, la evidencia de la minería prehistórica de estaño en Europa se borró rápidamente en el entorno fluvial. La evidencia circunstancial ha sugerido que los minerales de estaño del Erzgebirge a lo largo de la frontera germano-checa fueron explotados en la Edad de Bronce. Para investigar esto más a fondo, los minerales de estaño de los tres plutones Erzgebirge, así como Cornwall, fueron caracterizados y comparados isotópicamente con la composición isotópica del estaño de los artefactos de la región en la Edad del Bronce. Después de considerar el fraccionamiento isotópico asociado con el proceso de fundición, un enfoque probabilístico indica que, en la transición a la Edad del Bronce Media, el centro minero predominante era en el Plutón Central, pero la actividad minera se trasladó al Plutón Occidental durante el resto de la Edad del Bronce.
Introduction
Since the invention of extractive metallurgy in the Balkans 7,000 years ago, human technological and social development has been inextricably tied to the availability of mineral resources, as is evident in the fundamental three-age system of European prehistory: Stone Age, Bronze Age, and Iron Age. However, much of Europe’s ancient mining heritage remains to be discovered. Extensive bedrock mining of European copper, dating as far back as the Eneolithic (ca. 5000 BC), has been documented in Serbia and Bulgaria. Although extensive subsurface and open pit tin mines dating to the Bronze Age have been documented in arid regions of Iran, Central Asia, and Central Turkey, such mines are absent in Europe. This is due to the contrasting cli-
matic conditions. Weathering and fluvial processes associated with Europe’s temperate to Alpine climate produced placer tin deposits from the natural breakdown of bedrock ores. Being easier to work and requiring fewer resources, placer deposits were exploited rather than the nearby bedrock ores from which they were derived. Unfortunately, the wooden tools associated with sluicing and panning are unlikely to be preserved, and the mining process itself leaves only ephemeral scars (Tolksdorf et al., 2019). Consequently, the archaeological record of early tin mining in Europe has been largely erased in dynamic fluvial environments. Lead isotopes have been used in archaeological studies of copper ore provenance for
T
he discovery and characterization of mineral resources remains a cornerstone of applied Earth Science.
1 Department of Earth and Environmental Science, Brooklyn College – CUNY, 2 Department of Geology, Juniata College 3 Department of Archaeology, University of South Bohemia 4 Department of Anthropology and Archaeology, Brooklyn College 5 Department of Prehistory and Antiquity, National Museum in Prague 6 Department of Earth and Planetary Sciences, Rutgers University * wpowell@brooklyn.cuny.edu
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