Micro XRF

Elemental mapping of micromorphological block samples using portable X‐ray fluorescence spectrometry (pXRF): Integrating a geochemical line of evidence

“…Further, the potential for inclusions and voids to affect measurements and geochemical data visualization is an obvious limitation, though if inclusions are large enough they can be equally helpful in understanding site formation processes. Echoing Mentzer (), we note that detailed descriptions of each transect including void space or inclusions before any experiment is necessary. In cases where even higher resolution is needed, such Layer VII (Microfacies C) which was too thin to be adequately captured by our method, more high‐resolution methods such as µXRF (see Mentzer & Quade, ), macro‐XRF scanners, or core scanners could be applied.…”

“…In our experience, applying pXRF to block samples can introduce its own issues which must also be considered by the analyst. These include, (a) ensuring proper degree of impregnation quality (e.g., length of time and setting during curation), which can be affected by the porosity of sediments and soils, especially in regard to clay‐rich samples which commonly demand the need to use a vacuum for proper impregnation (Courty et al, , p. 58), (b) measuring the chemical composition of the resin, which can include trace amounts of V, Cr, Co, Na, Ni, Ge, and Sb (Mentzer, ; Nakano & Nakamura, ), (c) understanding that there is an inability to determine the presence of inclusions or voids directly beneath the sampling area, and (d) controlling for the potential effect of differences between sampled areas that have large inclusions versus small (e.g., CaCO 3 nodules which would have strong Ca absorption which may affect the ability to interpolate nearby measurements). By following proper impregnation and curation protocols (see Goldberg & Macphail, , pp.…”

“…80–96). Here, we follow Mentzer (), who discusses implementing a regular grid sampling plan overlying block samples when applying µXRF that we find equally useful when applying pXRF. The key difference here is that µXRF devices operate with computer‐operated and motorized sample ensuring both accuracy and precision, and therefore handheld methods are suspect to a higher degree of user error, especially when used without cameras.…”

“…Recent research has demonstrated that valuable geochemical and isotopic information can be obtained from block‐sample surfaces (Mentzer, ). In a study of carbonate‐rich deposits from the Pre‐Pottery Neolithic site of Aşıklı Höyük, for example, Mentzer and Quade (), applied micro‐X‐ray fluorescence spectrometry (µXRF) coupled with stable isotope analysis to a polished resin‐impregnated block sample at 0.1 mm spacing, which allowed the positive identification and differentiation of lime and plaster floor construction activities (Mentzer & Quade, ).…”

Raman scattering spectra of amber

“…It is known that for optical materials and their structures, one of the most important properties is the surface quality, since the roughness of the waveguides leads to scattering of light streams and, consequently, losses during the interaction of transmitted modes in the boundaries of the waveguides themselves. Thus, the increase in optical losses in devices as a result of scattering is proportional to the third degree of the difference in refractive indices between the core and the shell [6][7].…”