ELEMENTAL AND PB ISOTOPIC ANALYSIS OF ARCHAEOLOGICAL METALS BY LASER ABLATION-Q/MC-ICP-MS: METHODS RESTRICTIONS AND APPLICATION EXAMPLES

摘要

The use of laser-ablation (LA) systems coupled to ICP source instruments is becoming progressively common in archaeological studies as it allows for detailed minimally invasive analyses. We have set up improved microana-lytical procedures using those techniques for the determination of element contents and Pb isotopic ratios in archaeological metal artefacts, including natural raw materials. A full range of trace elements in archaeological metal objects and ancient coins were analysed with good precision and accuracy using a ?wet ablation? technique and a quadrupole ICP-MS instrument, allowing for reliable chemical discrimination among samples. Pb isotopic ratios were obtained on different types of metallic samples using a multicollector ICP-MS instrument. The isotopic results have also good precision and accuracy being reliable and meaningful in terms of geochemical and archaeological significance. Here we present the details of the implemented analytical methods that allow for element and Pb isotope chemical analyses of often highly valuable samples with minimum sample destruction.