Projects per year
Transportable energy dispersive X-ray fluorescence (XRF) spectrometers allow the elemental composition of coins to be measured at collections, enhancing security while maximizing access to historically important material. We assessed 10 silver coins, using five XRF spectrometers. We found no systematic differences between analyses using Mo- and Rh-anode tubes, and no substantial advantage using He flush over air for elements heavier than Ti. Higher voltage X-ray tubes enhanced analytical precision. Understanding patina composition made a numerical correction possible, allowing an approximation of the underlying coin metal with good results for metals including Cu, Ag, Au, Pb, and Bi.
- X-ray fluorescence spectrometry
- elemental analysis
- ancient history