High Resolution Elemental Mapping of a Meteorite Specimen

Composite net intensity map of a Mocs meteorite specimen showing a cracked surface with lead deposits (in red) concentrated within the cavities

Meteorites samples are rare and thus precious, they are preferably analyzed by non-destructive methods. When microscopic studies of pristine surfaces are the focus of research, common sample preparation steps for SEM-based EDS analysis such as cutting, grinding, polishing and carbon coating are strictly excluded.

Conventional EDS detectors are facing limitations under such circumstances, especially when high spatial resolution is required.  Since mineralogical meteorites specimen are non-conductive and topographic, charging and shadowing effects are the main challenges.

To overcome these limitations, a state-of-the-art solution is available with the XFlash® FlatQUAD. This unique annular EDS detector is placed directly above the sample similar to a BSE detector. It is characterized by an extremely high sensitivity for low X-ray yield, minimizing any shadowing effects and is thus a perfect tool for mapping rough, non-coated samples such as meteorites.

We investigated the Mocs meteorite, a historic fall of February 2, 1882 in Hungary, provided by the Natural History Museum in Vienna (NHM). Application of the XFlash® FlatQUAD shed light on the evolution of the cosmic material thanks to its ability for high resolution mapping of the elemental composition even within deep cavity. (Salge et al., EMAS 2018 - Microbeam Analysis in the Earth Sciences, Bristol, UK, pp.16)