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The nondestructive investigation of millimeter-sized meteoritic materials is often hindered by self-absorption effects. Using X-ray-based analytical methods, the information depth for many elements (Z < 30) is in the range of up to only a few hundred micrometers, and for low-Z elements (Z < 20), this is reduced even further to only a few tens of micrometers. However, the investigation of these low-Z elements, in particular calcium, aluminum, and magnesium, is of great importance to planetary geologists and cosmochemists, as these elements are regularly used to characterize and identify specific features of interest in extraterrestrial materials, especially primitive chondritic material. In this work, nonresonant inelastic X-ray scattering from core electrons was performed at beamline ID20 of the ESRF in a direct tomography approach in order to visualize these low-Z elements within the millimeter-sized meteoritic samples. The obtained 3D elemental distribution volumes were compared to results from X-ray fluorescence-CT and absorption CT experiments and were found to be in good agreement. Additionally, several regions of interest could be identified within the inelastic scattering volumes, containing information that is not available through the other presented means. As such, the proposed approach presents a valuable tool for the nondestructive investigation of low-Z elemental distributions within millimeter-sized extraterrestrial materials, such as the samples of the Hayabusa2 sample return mission.

This chapter focuses on the basic principles of X-ray fluorescence (XRF) and micro-XRF imaging applicable to cultural heritage research, presenting basic figures of merit and application examples based on the use of advanced laboratory and synchrotron radiation sources. Related methods of analysis making use of absorption edge phenomena by X-ray absorption spectroscopy, including X-ray absorption near-edge structure and extended X-ray absorption fine structure spectroscopy will also be discussed.

Analytical chemistry 92(1), 1106-1113 (2020). doi:10.1021/acs.analchem.9b04176, Detection of rare earth elements (REE) is commonly performed with destructive techniques such as (LA)-ICPMS or coupled to a destructive sample preparation. When investigating unique geological samples, such as cometary, asteroidal, or interstellar material from sample return missions or inclusions in deep Earth diamonds, a nondestructive method is preferred. The presented nondestructive highly sensitive wavelength-dispersive X-ray fluorescence spectroscopy (WD-XRF) technique is designed to measure the L-lines of REE between 4.5 and 7 keV with a sensitivity down to the ppm level. REE fluorescence L-lines are often only separated by a few eV from neighboring XRF-lines and cannot be resolved by an energy dispersive approach especially in the presence of transition metal K-lines. In our spectrometer the characteristic X-rays emitted by the sample are dispersed by a fixed Ge(111) analyzer crystal over the active area of an energy dispersive pn-charge-coupled-device (pnCCD) detector, enabling high energy resolution detection of X-rays differentiated by their corresponding Bragg angles. The use of an energy-dispersive 2D detector enables the simultaneous acquiring of XRF-lines while eliminating any ambiguities due to potential contribution from higher order diffraction effects or other diffraction planes and thereby increases the sensitivity by reducing the (scatter) background. This detection method shows an energy resolution of 12 eV for the Ti–Kα fluorescence line and has a sensitivity down to 0.50 ppm for REE L-lines. The method was optimized specifically for the nondestructive analysis of inclusions in deep Earth diamonds, yielding in situ quantitative information about up-to-now inaccessible elemental (REE) composition patterns together with the more abundant transition metals like Ti, Cr, Mn, and Fe. This information is of great importance to decipher the role that deep Earth plays in the global carbon and fluid cycle., Published by American Chemical Society, Columbus, Ohio

This study aims to characterize the Neolithic ceramics (Mushki, Bashi, and Jari wares) of the Kur River Basin and reconstruct the origin of the raw materials and manufacturing technology. Neolithic ceramics from 13 different sites have been studied with handheld X-ray fluorescence (hXRF) spectroscopy and thin section petrography. The geochemical signature of these ceramics was defined, and four compositional groups were determined. The variation in these compositional groups most likely relates to the ceramic wares for the Mushki and Bashi ceramics and to the site or group of sites for the Jari ceramics. Additionally, sediment samples were studied with hXRF demonstrating the variability in the geochemistry of the area. To determine the composition of the slips used for Bashi and Jari ceramics and to compare them with the inner fabric of the vessels, micro X-ray fluorescence (μXRF) spectroscopy was applied. The combination of these archaeometrical techniques indicated the use of unaltered, fine-grained, and mainly alluvial clays without the addition of temper (except for chaff) for the production of the three studied wares and the use of different clay types through the Neolithic in the Kur River Basin.