TY  - JOUR
TI  - Mineralogical and gemmological characteristics of garnets associated with xenoliths
within trachyte dome, Hisarlıkaya (Ankara), Central Anatolia, Turkey
AB  - Garnet-bearing xenoliths are observed within a trachytic dome extrusion in the Hisarlıkaya region (Ankara). These garnets
exhibiting greenish-reddish-dark brown colour and ranging in sizes up to 1 cm were examined in terms of mineralogical, geochemical,
and gemmological characteristics. Mineralogical studies indicate that these garnets (And 88-93 Grs 7-12) are linked to solid solution series,
which are dominantly andradite with lower content of grossular. According to major, trace, and rare earth element (REE) analysis, the
representative garnet crystal shows high CaO, Fe2
O3
, Al2
O3
, MgO, MnO, V, W, and light rare earth elements (LREE) concentrations.
These high concentrations might indicate the mobility of these elements during skarn formation related with contact metamorphism,
material exchange occurring via hydrothermal fluids, site geometry of the crystal, ionic radius of cations, and charge balance.
The Hisarlıkaya garnets display dodecahedron-trapezohedron crystal habits with good translucency, glassy, transparent features, and
also optical isotropic character. Their refractive indices are high (>1.78), and specific gravities range from 3.66 to 3.67 g/cm3
. These
garnets are not suitable for use as gemstones since they cannot be cut or processed considering all the mineralogical properties of
garnets.
AU  - TATAR ERKÜL, Sibel
AU  - Kulahci, Gullu Deniz
AU  - varol, elif
DO  - 10.3906/yer-2006-14
PY  - 2021
JO  - Turkish Journal of Earth Sciences
VL  - 30
IS  - 3
SN  - 1300-0985
SP  - 379
EP  - 391
DB  - TRDizin
UR  - http://search/yayin/detay/521427
ER  -