Mineralogical, geological and geochemical properties of Au occurrences related to arsenopyrite in Guneykoy (Esme-Usak) area

Aksaray University of Science and Technology Institute of Geological Engineering Department, prepared a thesis in this study which is in Esme (Uşak), arsenopyrite veins are examined in terms of geological, petrographic, geochemical properties, fluid inclusion and sulfur isotope. The study area in Western Anatolia, is located in metamorphic rocks that make up the Menderes Massif. Arsenopyrite-quartz veins of old gneiss and mica schist of Precambrian Menderes Massif is located within the study area. The main ore mineral is arsenopyrite. Arsenopyrite which mainly consist of amorphous and / or semi euhedral cataclastic featured, are observed. Mostly grain size of arsenopyrite range from 5-150 micrometers. There is pyrite in fractures in the arsenopyrite or among the arsenopyrite. Some of the pyrite minerals turned to marcasite and some of them turns to limonite. Gold mineralization occurs in arsenopyrite as an inclusion. Gold grain size is 30-100 µm. It is seen in some quarters as a single grains of gold, and some cut into smaller grains are observed in the group of arsenopyrite. According to the results of the analyzes of the content of the ore samples Au grade ranges from 0.5 ppm to 10 ppm; Ag content of 20,4 to 0.1 ppm, Ni content of 156 to 20 ppm; Cu content of 9.0 to 19.9 ppm; Pb content of 363 to 6.2 ppm; Zn content of 2 to 32 ppm; As content greater than 1000 ppm; Cd content was determined to be about 0.1 ppm. S34 % values of the arsenopyrite varies in the range -3.7 -10.6. These data indicate that supply of sulfur from the local host rocks and igneous rocks is limited. Quartz and calcite samples taken from the quartz veins with arsenopyrite minerals to study the fluid inclusion. According to this study, fluid which create the mineralization has 270-440 0C homogenization temperature