X-ray fluorescence scanning of discrete samples - An economical perspective

We measured discrete, powdered, homogenized samples from geochemical reference standards (GRS) and from a loess-paleosol sequence (LPS) with an ITRAX XRF core-scanner. The objective is to highlight cost- and time-efficiency of X-ray fluorescence (XRF) scanning of discrete samples in comparison to conventional XRF. Based on data precision (mainly < 4% mean relative standard deviation) and data reliability (often R-2 >= 0.9) tests with six different measurement times (1, 5, 10, 30, 60 and 100 s) and two different X-ray tubes (Mo, Cr), reasonable minimal measurement times for thirteen considered elements were assessed. Accordingly, we designed test case scenarios for 10, 30 and 100 s measurement time in comparison to conventional XRF analysis with regard to cost- and time-efficiency. As long as qualitative geochemical data are sufficient for scientific research questions at hand, XRF scanning of discrete samples is proven to be more efficient by factors of 15-23 as to time and by factors of 4.5-51 as to cost when compared with conventional wavelength-dispersive (WD)-XRF analysis commonly applied to discrete samples. This underlines XRF scanning of discrete samples as a versatile, non-destructive qualitative geochemical screening tool with unprecedented time-and cost-efficiency. Such efficiency will foster application of this technique in a broad scientific field including e.g. terrestrial paleoenvironmental reconstructions and/or environmental pollution studies.