Abstract
In order to obtain a better understanding of fluorite deposits, rare earth impurities have been analyzed for a large number of samples taken from cross-sections of several low temperature hydrothermal veins. Two types of measurements have been used: Electron Paramagnetic Resonance (EPR) and Neutron Activation Analysis (NAA). For Gd, the ratio of spin concentrations to total concentration [Gd3+]/[Gdtotal] is close to 1 in all the samples; on the other hand, the ratios [Eu2+]/[Eutotal] and [Ce3+ -F i− ]/[Cetotal] exhibit large variations. The first result suggests that the major part of the lanthanides in the samples is incorporated in the crystal lattice and that clustering of lanthanides ions is not important. The behaviour of Eu and Ce is ascribed to charge state changes and symmetry state changes respectively.
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Méary, A., Galland, D., Chatagnon, B. et al. A study of Gd, Ce and Eu impurities in fluorite deposits by electron paramagnetic resonance and neutron activation analysis. Phys Chem Minerals 10, 173–179 (1984). https://doi.org/10.1007/BF00311474
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DOI: https://doi.org/10.1007/BF00311474