Determination of PGE and Re in archaeological bronzes: New ways to determine the origin of archaeological copper alloys*

A method for determining the platinum‐group elements (PGEs) and rhenium (Re) in archaeological bronzes was developed. For 20 mg of sample, detection limits of 0.07 (Re) to 1.4 (palladium; Pd) ng g –1 were achieved. The method was tested on standards and compared with measurements determined by the PGEs via matrix separation. The method was applied to 45 samples from the Bronze Age to the Middle Ages. In the process, the PGEs provided no further information for the Bronze Age samples. The samples from the Hallstatt and La Tène Period show increased contents of Pd and platinum (Pt). These contents distinguished the samples from all other samples and give an important indication of the possible ores used. Three groups can be distinguished in the Middle Ages by their Pd and Pt contents. One group falls into the field of Bronze Age samples. The other two groups have significantly higher Pd and Pt contents. One group has higher Pd than Pt contents, while the other group has exactly the opposite. In a sample, it is possible that the high contents of Pd and other PGEs indicate the use of copper shale in the Eisenach area.