Basics, possibilities and limitations of the microscopic X-ray fluorescence analysis

Microscopic X-ray fluorescence (MXRF) analysis was used to investigate diff erent samples: meteorites, Jasper. coated glas and, reference materials. Th e element distribution within sections of two different meteorites have bee n determined - one metal rich and one oxide rich. The metal rich showed a m atrix of Fe with Ni-, Ti-. and Si-enriched regions. The oxide rich also sho wed a Fe rich matrix and regions with different concentrations of other ele ments. A reference sample with a flat and polished but systematically tilte d surface was used to assure, that roughness of the sections of the meteori tes has only negligible influence. Nondestructive investigations in Jasper with included Stromatolithes, which were fossilized more than 2 billion yea rs ago showed the Stromatolithes to have Fe as main element instead of Si i n the Jasper matrix. The thickness of Yb-layers on glas was determined from the intensity of the Yb fluorescence peak. Calibration was done by using a sample without coating and a reference sample whose thickness of the layer was determined by XRD reflectometry. Futhermore it has been shown that mat erials can be analysed even if mounted in glas capillaries or covered by pl astic foils. By using Mark capillaries the elements from S to U may be dete cted instead of Na to U while working in vacuum mode.