Non-destructive micro-analytical system for the study of the manufacturing processes of a group of gold jewels from “El Carambolo” treasure

The impressive gold treasure of El Carambolo, representative of the Tartesic culture and dated from the 8th to 6th century BCE, constitutes a typological and stylistic unity unparalleled in the archeological field. Due to the importance of this treasure and the interest in studying it in depth, a new micro X-ray fluorescence (micro-XRF) portable system has been developed at the Centro Nacional de Aceleradores (Sevilla, Spain). Eleven jewels of El Carambolo treasure have been analyzed in order to characterize the composition of the employed alloys, to identify the manufacturing processes and to discuss hypothesis about the production workshop of the treasure. Besides, the application of the new micro-XRF instrumentation allowed the analysis of small details like decoration elements and joining areas. This study permits the characterization of the joining methods and manufacturing procedures, thus, the construction stages of these highly complex jewels can be inferred. Many archeological and historical studies of the treasure have been performed during the last years but very few analytical results have been published. Furthermore, the results demonstrate the capability of the new developed portable micro-XRF setup to substitute satisfactorily other micro-analytical techniques, such as micro-PIXE (Particle Induced X-ray Emission), when the sample cannot be brought to a laboratory. •Detailed analytical study of an important gold treasure from the south of the Iberian Peninsula has been performed.•A portable micro-XRF system has been developed and implemented for that purpose.•The equipment presents a very good spatial resolution, as the analysis of joining areas and small decorations was mandatory for a satisfactory study of gold jewels.•A group of 11 gold jewels belonging to the El Carambolo treasure has been analyzed. The alloys used as well as the production techniques have been studied.•The results obtained have shown a good homogeneity in the alloys composition and the use of the fusion welding, autogenous welding and brazing as soldering/welding methods.