A multimodal microcharacterisation of trace ‐element zonation and crystallographic orientation in natural cassiterite by combining cathodoluminescence, EBSD, EPMA and contribution of confocal Raman‐in‐SEM imaging

We present a multitechnical approach to chemical and structural data that includes scanning electron microscopy (SEM)‐based imaging and microanalysis techniques such as: secondary and backscattered electrons, cathodoluminescence (CL), electron probe microanalyser (EPMA), electron backscattered diffraction (EBSD) and confocal Raman‐imaging integrated in a SEM (RISE). The presented results show the complementarity of the used analytical techniques. SEM, CL, EBSD, EPMA provide information from the interaction of an electron beam with minerals, leading to atomistic information about their composition, whereas RISE, Raman spectroscopy and imaging completes the studies with information about molecular vibrations, which are sensitive to structural modifications of the minerals. The correlation of Raman bands with the presence/absence of Nb, Ta, Fe (heterovalent substitution) and Ti (homovalent substitution) is established at a submicrometric scale. Combination of the different techniques makes it possible to establish a direct link between chemical and crystallographic data of cassiterite. Lay description Tin is a metal that has been used commercially since the Bronze Age. Cassiterite (SnO2), a natural tin oxide, has been the most important source of tin (Sn) since that time. Sn is also associated with other metals such as titanium (Ti), niobium (Nb), tantalum (Ta), indium (In), tungsten (W), iron (Fe), manganese (Mn), mercury (Hg) in cassiterite. A thorough knowledge of its mi...
Source: Journal of Microscopy - Category: Laboratory Medicine Authors: Tags: Original Article Source Type: research