| Summary: | The grossular garnet from rodingite-type rock from the Suva Česma area in western Serbia is characterized with its weak anisotropic nature. Because its anisotropy could indicate a non-cubic lower symmetry, SEM-EDS and Rietveld powder refinement methods were used. The SEM-EDS results have shown that the garnet has a (Ca<sub>3.00</sub>Mn<sub>0.01</sub>)<sub>3.01</sub>(Al<sub>1.82</sub>Fe<sub>0.15</sub>Ti<sub>0.02</sub>)<sub>1.99</sub>(Si<sub>2.97</sub>Al<sub>0.03</sub>)<sub>3.00</sub>O<sub>12</sub> chemical composition (i.e., Grs<sub>91</sub>Adr<sub>08</sub>), which can be more specifically explained as ferric iron containing grossular. The next step further used Rietveld powder refinements of the various crystal structures in the <i>Ia</i>‾3<i>d</i>, <i>R</i>‾3<i>c</i>, <i>R</i>‾3, <i>I</i>4<sub>1</sub>/<i>a</i>, <i>Fddd</i>, <i>C</i>2<i>/c</i>, and <i>I</i>‾1 space groups as well as a single mixture, which was followed by a comparative analysis of the <i>R</i>-values, site occupancy factors, and bond lengths and angles. The synthesis of these results showed both that the studied grossular garnet is not cubic and that it crystallized in the disordered <i>Fddd</i> space group with the final <i>R</i><sub>B</sub> = 5.29% and <i>R</i><sub>F</sub> = 1.75%. It was presumed that the grossular formed at temperatures between 150 and ~600 °C.
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