The chemical, physical, and gemological properties of attractive rhodonite-rich rocks from Tanatz Alp (Switzerland) were investigated using classical gemological methods, petrographic observation, and analytical techniques such as X-ray powder diffraction, Raman spectroscopy, and scanning electron microscopy. The color of the samples varied from pale pink to purplish pink; they were opaque and contained braunite, rhodochrosite, and spessartine. The gem-quality samples have an attractive color and are compact with no fractures. Tanatz Alp rhodonites are characterized by the presence of other minerals such as kutnohorite, spessartine, ankerite, rhodochrosite, khristovite-(Ce), pyroxmangite, and chlorite. The presence of the polymorph pyroxmangite was also confirmed by micro-Raman analyses. The samples had a chemical composition of MnO (45.97–48.64 wt.%) and SiO2 (46.70–47.92 wt.%), with very low amounts of MgO (0.64–1.65 wt.%) and CaO (<5 wt.%). Rhodonites from Tanatz Alp have some economic importance because of their use in jewelry and ornamental objects.
RHODONITE-PYROXMANGITE FROM TANATZ ALP, SWITZERLAND
Caucia F. P.
Conceptualization
;Marinoni L. T.Methodology
;Riccardi M. P.Investigation
;
2020-01-01
Abstract
The chemical, physical, and gemological properties of attractive rhodonite-rich rocks from Tanatz Alp (Switzerland) were investigated using classical gemological methods, petrographic observation, and analytical techniques such as X-ray powder diffraction, Raman spectroscopy, and scanning electron microscopy. The color of the samples varied from pale pink to purplish pink; they were opaque and contained braunite, rhodochrosite, and spessartine. The gem-quality samples have an attractive color and are compact with no fractures. Tanatz Alp rhodonites are characterized by the presence of other minerals such as kutnohorite, spessartine, ankerite, rhodochrosite, khristovite-(Ce), pyroxmangite, and chlorite. The presence of the polymorph pyroxmangite was also confirmed by micro-Raman analyses. The samples had a chemical composition of MnO (45.97–48.64 wt.%) and SiO2 (46.70–47.92 wt.%), with very low amounts of MgO (0.64–1.65 wt.%) and CaO (<5 wt.%). Rhodonites from Tanatz Alp have some economic importance because of their use in jewelry and ornamental objects.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
