Trace element analysis of metallic artifacts from Gedikli hoard by atomic absorption spectroscopy

Abstract

The object of this study was to determine the trace and alloying elements of the metal artifacts recovered from Gedikli during excavation between 1964-1967. Most of the artifacts were from a cremation burial sight dated to Early Bronze Age, which includes pins, awls, ring , bracelets etc. About 20-25mg. samples, obtained from over 100 artifacts by drilling, are analysed using atomic absorption spectroscopy. The results showed that most of the samples were copper and copper alloys. Both tin and arsenic were present as an alloying element in some samples at about 7% and 5% respectively. Nearly half of the objects had both tin and arsenic together but at about 1% or less.Silver and iron were the other two elements that were present in almost all samples at trace levels. Zinc and lead concentrations were quite variable from trace levels to up to 27,4% and 15,5% respectively. Artifacts are classified according to type, shape and to presence or absence of certain elements. Histograms, correlations and cluster analysis were carried out on the trace element distribution of these groups to determine particular trends, manufacturing techniques and common are sources. The results showed that, there was no general trand in the trace element distribution in general for all artifacts. However, certain trends could be observed when artifacts are arrand-ged into subgroups. Umbrella headed pins were all tin bronzes with similar trace metal distribution. Two clusters were also observed between artifacts having tin, arsenic, lead and nikel elements which may indicade two different are sources. Even though the artifacts recovered, cover a relatively short time span, the heterogeneity of the trace element distribution could be an indication of different are sources, manufacturing techniques and trade routes. A complete examination of the sight will show if the objects are locally manufactured or not. Chronological arrangement of the artifacts would yield information on the technological development as well as on trade relations. This preliminary study shows that complete excavation of Gedikli could bring light to the metallurgy of the Bronze Age in the area.