9-1 Reinterpretation of the Raman Spectrum of Kimzeyite

Session: Early Career Investigators in Mineralogy and Crystallography

Presenting Author:

Authors:

Abstract:

Kimzeyite (Ca₃Zr₂(SiO₄)(AlO₄)₂) is a zirconium-rich garnet that is classed within the schorlomite group of garnets. Kimzeyite is a relatively rare mineral, found only in a handful of localities throughout the world, and is commonly associated with alkaline, silica-undersaturated igneous rocks that are highly evolved, such as intrusive carbonatites and ultra-mafic lamprophyre dikes. Despite its interesting mineralogical qualities and geologic settings, there is a paucity in the literature regarding the Raman spectra of kimzeyite. To date, only one paper has been published (Schingaro et al. 2001) and their Raman band assignments are somewhat tentative. Therefore, we undertook the first symmetry adapted mode analysis of single-crystal kimzeyite, combined with polarized Raman spectra, to better constrain the band assignments via selection rules. Our results show that the Raman bands at 503 cm^-1 and 837 cm^-1 are both A₁g symmetry modes, in agreement with the assignment by Schingaro et al., (2001). However, the Raman band at 307 cm^-1 is a T₂g symmetry mode, which disagrees with its previous tentative assignment to the A₁g mode (Schingaro, 2001).

Schingaro, E., Scordari, F., Capitanio, F., Parodi, G., Smith, D., Mottana, A. (2001). Crystal chemistry of kimzeyite from Anguillara, Mts. Sabatini, Italy. European Journal of Mineralogy, 13 (4): 749–759.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-7729

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