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Garnets are observed as phenocrysts in blocky rhyolites of Cumaovası Volcanites and are reddish-blackish in color, show vitreous luster, and have dodecahedron forms varying between 0.5 and 2.0 cm in size. In optical microscope investigations, they exhibit fractured structures and contain quartz, hematite, chlorite, and acicular rutile inclusions. Garnet phenocrysts are highly consistent with spessartine-type garnet end members in the Raman spectrum. This result is supported by the mineral chemistry results determined as spessartine (Sps)0.50–0.52 almandine (Alm)0.47–0.48 grossular (Grs)0.01–0.02. In the chondrite, primitive mantle, and Mid-Oceanic Ridge Basalt normalized multi element variation diagrams, garnet phenocrysts show enrichment in all elements (except Sr, K, P, and Ti). In contrast, in the upper continental crust normalized multi element variation diagram, garnet phenocrysts show depletion in large ion lithophile elements (Rb, Ba, K, and Sr) relative to high field strength elements. They exhibit slight enrichment in light rare earth elements ((La/Sm)N = 0.11–1.07) relative to heavy rare earth elements ((Sm/Yb)N=0.78–0.97). Furthermore, garnet phenocrysts have significant negative europium (Eu) ((Eu/Eu*)N = 0.01–0.02) and mildly positive cerium ((Ce/Ce*)N = 2.43–13.77) anomalies indicating hot and reduced magma conditions. The Y/Ho ratios have ranged from 18.9 to 20.3 and are close to the chondrite value. The zircon saturation temperatures (TZr) of the garnet's host rock was determined to be 756 °C. As a result of mineralogical, geochemical and gemological studies, it was concluded that Görece garnet phenocrysts have glassy luster and semi-transparent dodecahedral crystal shapes, so they can be classified as semi-precious gemstones. In addition, the rare earth element content of the garnet phenocrysts is similar to that of industrial garnet sands and it is thought that they may have potential. [ABSTRACT FROM AUTHOR]

Ancient period naturalist Plinius referred that almandine composition Lal Stones (Granat) which had been widely used in the Hellenistic and Roman periods, were extracted from Alabanda (Çine) and Orthosia (Yenipazar) in Karia in Anatolia. The garnet samples, which are the subject of this study, are found in the middle-high grade, gneiss, and mica-schist in the Menderes Massif in Hacıaliler (Çine-Aydın) region. Purplish-brown and matt garnet porphyroblasts, varying between 0.5-2 cm in size, have crystallized in dodecahedron form. Garnet minerals, display poikloblastic texture in microscopic examinations, are in a highly fractured structure and contain plenty of quartz, muscovite, and opaque mineral inclusions. In line with a non-destructive analysis technique, Confocal Raman Spectroscopy studies, it has been determined that garnets present a total of 10 different Raman vibrations, 910-912, 349 and 553-555 cm-1 strong, and are typically in almandine composition. According to the results of mineral chemistry, garnets have the chemical formula of Alm0.72-0.87 Grs0.07-0.19 Pyr0.02-0.13 Sps0.00-0.02. In accordance with garnet-biotite geothermometer calculations, it was determined that garnets are formed at an average temperature of 565.3±20.8 °C and under the pressure of 6.6 kbar. It was concluded that Hacıaliler garnets demonstrated depletion in terms of LIL elements (Cs, Rb, Ba, K, Sr, Pb) in the average continental crust (MCC) multi-element variation diagram. It was discovered that garnet samples demonstrated enrichment in terms of REE (∑REE: 192.2-212.1), (La/Sm)N ratio 2.62-2.89, (Sm/Yb)N ratio 0.31-0.38 and (Eu) /Eu*)N ratio vary between 0.41-0.44 in REE multi-element variation diagram normalized to chondrite. According to the non-destructive gemological tests, the specific gravity of garnet crystals varies between 3.33 and 3.64, and the refractive index values were found to be around 1.80-1.81. According to the L*a*b* color system, the color average of garnet crystals was determined to be as L*: 46.25 a*: 6.55 b*: 6.60 (purplish brown). As a result of mineralogical, geochemical, and gemological evaluations, it has been concluded that Hacıaliler garnet samples have undergone multi-stage metamorphism and have lost their bright and transparent crystal forms through the subsequent geological processes (weathering, alteration, etc.); therefore, they do not present the characteristics of gemstones. In addition, it is thought that garnet samples may have an important potential in terms of their REE contents. [ABSTRACT FROM AUTHOR]