Tracing Medieval and Renaissance Alabaster Works of Art Back to Quarries: A Multi-Isotope (Sr, S, O) Approach

Multi-isotope fingerprinting (sulphur, oxygen and strontium isotopes) has been tested to study the provenances of medieval and Renaissance French and Swedish alabaster works of art. Isotope signatures of historical English, French and Spanish alabaster source quarries or areas are revealed to be highly specific, with a strong intra-group homogeneity and strong inter-group contrasts, especially for Sr and S isotopes. The chosen combination of isotope tracers is a good basis for forensic work on alabaster provenance, allowing verification of hypotheses about historical trade routes as well as identification of fakes and their origin. The applied analytical techniques of continuous flow isotope ratio mass spectrometry (CF–IRMS) and thermal ionization mass spectrometry (TIMS) only require micro-samples in the low-milligram range, thus minimizing the impact on the works of art.