X‐ray fluorescence spectroscopy and Monte Carlo simulation for quantitative characterization of Bolivian pre‐Hispanic golden artefacts

Abstract

The quantification of archaeological artefacts with X-ray Fluorescence is quite complex because it demands some calibration procedure. It is also rather more challenging when the customization of the portable equipment for in situ measurements is required. The objective of this study was to introduce a quantitative method by performing a calibration curve for a ternary gold alloy (Au, Ag and Cu). Fast Monte Carlo simulation combined with in situ portable XRF (pXRF) measurements in order to circumvent the calibration requirement using standard reference materials was used. Measurements with a laboratorymade equipment were taken from a set of 16 pre-hispanic gold alloy artefacts of a collection from the Museo Nacional de Etnografia y Folklore, La Paz, Bolivia. The spectra simulation was conducted with the XMI-MSIM software. The results demonstrated that the combined use of pXRF measurements and spectra simulation via Monte Carlo is a feasible method for gold alloy quantification. In the examined samples, the Cu content was below 5% and for Au it ranged from 13 to 100%. Moreover, some peculiarities of the artefacts archaeological context were discussed.

Monte Carlo Simulation Aided Quantitative Laboratory X-ray Fluorescence Analysis and Its Application in Provenancing Studies for Geo-Archeological Samples

“…The XRF spectra were analyzed using the AXIL algorithm, a linear least square fitting procedure, yielding the intensity for each detectable element in the samples. To establish a fast quantification method for the described spectrometer, a MC simulation aided quantification method was used. , …”

“…To establish a fast quantification method for the described spectrometer, a MC simulation aided quantification method was used. 8,34 The first step involved building the virtual version of the instrument using scans on three different reference materials (NIST SRM 2709a, NIST SRM 1577c, and MPI DING ATHO-G). 32 These materials were chosen since they have very different matrices, being a soil sample, organic material, and basalt glass, respectively.…”

Atomic spectrometry update – a review of advances in X-ray fluorescence spectrometry and its special applications

“…Although both systems could be recommended for in situ campaigns in cultural heritage studies, the two-beam mode of the second system allowed a better detection of low- Z elements, as was to be expected. Melquiades et al 110 combined the use of pXRF measurements and Monte Carlo spectral simulation for quantitative evaluation of 16 golden artefacts from the Museo Nacional de Etnografia y Folklore (La Paz, Bolivia). The spectra simulation was conducted with the open source XMI-MSIM software.…”