A technological study of a bronze pins collection of geometric period from the sanctuary of Athena Alea at Tegea

Abstract

A collection of 47 copper alloy artifacts from the sanctuary of Athena Alea at Tegea, dating to the 9th-7th centuries BC, was studied and chemically analysed with handheld p-XRF, μXRF and SEM-EDS to determine the alloy type that was used for their production. The collection consists of Cu-Sn binary alloys. The relative concentration of the two metals does not seem to have been determined by the type of artifact the alloy was used to produce. The results also imply that fresh rather than scrap metal was used. The majority of the artifacts is made of bronze with an average tin content of approximately 11%. There is, however, an object which was found to have a significantly lower tin concentration, which averages 0.3% Sn. The lead content in the assemblage ranges from 0.5 to 4.94%. Because lead concentrations in the Helladic and the extended Balkan area are significant, their presence is interpreted as a non deliberate addition. The iron content ranges from 0.02 to 1.10%, while nickel exhibits a concentration range between 0.03 - 0.34%. Both elements are believed to be non-intentional additions to the alloys, resulting from the smelting process and originating in the copper ores. Arsenic is detected in all artifacts, in a mean concentration of 0.17%. The limited amount of arsenic may be the result of the use of arsenic-rich copper ores and less likely can be interpreted as evidence for the possible use of recycled metal deriving from artifacts dating to the Bronze Age. The present study provides evidence concerning the continuity of the use of bronze with high tin content in the area of Tegea during the Geometric and Orientalizing periods.