ARSENICAL COPPER: AN ALLOY BEFORE BRONZE IN SW IBERIAN PENINSULA?
The research concerning MBA artefacts in Southern Portugal has significantly increased the knowledge on the manufacture and use of arsenical copper alloys. Related archaeological contexts were radiocarbon dated to the first half and the third quarter of the second millennium BC, while no distinction was found between the composition and manufacture of tools and weapons from distinct funerary practices and domestic contexts. Moreover, the composition of artefacts shows a strong evidence for the preference of high arsenic contents (c. 4 wt%). A Gaussian distribution of arsenic contents clearly indicates an evolution from Chalcolithic metallurgy in southern Portugal and neighbouring regions. Regardless of the method used to obtain the alloy, there seems to have been a growing awareness amongst MBA metallurgists of the aesthetic and practical value of arsenical copper, which indirectly reveals the growing importance of metal among those prehistoric communities.
R. Orestes Vidigal, P. Valério, M.F. Araújo, A.M.M. Soares, R. Mataloto, 2016. Micro-EDXRF study of Chalcolithic copper-based artefacts from Southern Portugal. X-Ray Spectrometry 45, 63-68 (DOI: 10.1002/xrs.2658).
P. Valério, R. Orestes Vidigal, M.F. Araújo, A.M.M. Soares, R.J.C. Silva, R. Mataloto, 2016. The manufacture of copper weapons and tools from the Chalcolithic settlement of São Pedro (Portugal). Materials and Manufacturing Processes (DOI: 10.1080/10426914.2016.1198030).
P. Valério, A.M.M. Soares, M.F. Araújo, R.J.C. Silva, L. Baptista, 2016. Middle Bronze Age arsenical copper alloys in Southern Portugal. Archaeometry 58(6) 1003-1023 (DOI: 10.1111/arcm.12212).
P. Valério, A.M.M. Soares, M.F. Araújo, R.J.C. Silva, E. Porfírio, M. Serra, 2014. Arsenical copper and bronze in Middle Bronze Age burial sites of southern Portugal: the first bronzes in Southwestern Iberia. Journal of Archaeological Science 42, 68-80 (DOI: 10.1016/j.jas.2013.10.039).