CHARACTERIZATION OF MINERALS (PLATINUM-GROUP, ARSENIDES, TELLURIDES, SULPHIDES) USING BENCHTOP MICRO-XRF AND COMPUTER-CONTROLLED SEM-EDS WITH SDD

摘要

A combination of Energy dispersive spectrometry (EDS) on scanning electron microscope (SEM) with bench top Micro-XRF enhances data generation for mineralogical applications. Samples with sizes up to 20x16 cm can be analyzed by Micro-XRF within 4 h to locate regions of interest for further high-resolution SEM studies. Using SEM-EDS feature analysis, grains >4μm in size can be classified throughout an entire thin section within less than 2 h. Features at the sub-μm scale in bulk samples can be analyzed by using low accelerating voltages.Applications: (1) The existence of high demand elements in samples from an offset dike of the Sudbury Igneous Complex can be determined by uXRF. Low voltage SEM-EDS analysis provides new insights for S, Te and As deposit models. (2) Platinum-group minerals: Grains down to 500 nm in size can be classified by feature analysis using an accelerating voltage of 6 kV at 100 nm BSE pixel resolution.