Estimation of Li and OH contents in (Li,Al)-bearing tourmalines from Raman spectra

Author(s)
Adam Pieczka, Bozena Golebiowska, Marcin Stachowicz, Krzysztof Nejbert, Jakub Kotowski, Piotr Jelen, Andreas Ertl, Krzysztof Wozniak
Abstract

Six Al- and Li-bearing tourmaline crystals from pegmatites were structurally and chemically characterized. These samples can be assigned to elbaite, fluor-elbaite and rossmanite. Quantitative analyses of light elements such as Li, B and H are not always easily accessible. Therefore a method for the calculation of Li and OH would be of a general interest for the Geosciences. In the present work we test whether relatively accurate Li and OH estimations are possible based on the deconvolution of the O–H stretching vibration modes in a Raman spectrum on common (Al, Li)-rich tourmalines. We use the short-range arrangement model in our band interpretation as this model, in contrast to other models, provides the ability to evaluate an additional parameter by analyzing the OH stretching modes that can be used in the formula calculation process, which ultimately leads to the estimation of Li and OH with high accuracy. We also compare microprobe and Raman spectroscopy results, which we combine, with optimized data derived from microprobe and single-crystal structure refinement by using the same crystals. Based on our investigations, where the Raman spectra were recorded on non-oriented crystal sections, we conclude that we produce more accurate estimations, when the effects of the section orientation are considered. Therefore, we also propose a new method to correct the influence of the orientation of the crystal section.

Organisation(s)
Department of Mineralogy and Crystallography
External organisation(s)
AGH University of Science and Technology, University of Warsaw
Journal
Mineralogy and Petrology
Volume
116
Pages
229-249
No. of pages
21
ISSN
0930-0708
DOI
https://doi.org/10.1007/s00710-022-00774-2
Publication date
04-2022
Peer reviewed
Yes
Austrian Fields of Science 2012
104026 Spectroscopy, 105116 Mineralogy
Keywords
ASJC Scopus subject areas
Geochemistry and Petrology, Geophysics
Portal url
https://ucrisportal.univie.ac.at/en/publications/6c6476cc-892a-409b-9c93-01ed99ae6130