Azevedo-Vannson, S., Remusat, L., Bureau, H., Béneut, K., Cesare, B., Khodja, H., Jiménez-Mejías, M., & Roskosz, M. (2022). NanoSIMS determination of the water content of staurolite. Rapid Communications in Mass Spectrometry, n/a(n/a), e9331. https://doi.org/https://doi.org/10.1002/rcm.9331
Staurolite is an important mineral that can reveal much about metamorphic processes. For instance, it dominates the Fe-Mg exchange reactions in amphibolite-facies rocks between about 550 and 700 °C, and can be also found at suprasolidus conditions. Staurolite contains a variable amount of OH in its structure, whose determination is a key petrological parameter. However, staurolite is often compositionally zoned, fine-grained, and may contain abundant inclusions. This makes conventional water analysis (e.g. FTIR or by chemical titration) unsuitable. With its high sensitivity at high spatial resolution, NanoSIMS is potentially a valuable tool for determining water contents in staurolite. However; a calibration with relevant standards covering a large range of water content is required to obtain accurate and reliable analyses, because matrix effects typically prevent direct quantification of water content by SIMS techniques.