Arık, FetullahTurhal, Erhan2024-05-242024-05-242018https://hdl.handle.net/20.500.13091/5554The study area covers the area between Görümlü-Kuruseki and Almus District borders to the north of Almus Dam Lake, 36 km west of Tokat province. Tokat province is rich in good quality semi-precious stones such as jasper, wood opal, chalcedony, agate, chrysoprase, quartz, agate etc. formation. There are very high-quality chalcedony and agate formations in Turhal- Tokat and Almus line. The aim of the study was to determine the geological characteristics of the region of Almus (Tokat) and its vicinity, to determine the distribution areas of agate formation in the region, to investigate the relations with the geological units, mineralogical-petrographic features and processability of agates. In the region of Almus (Tokat), the basement is composed of the Paleozoic-Mesozoic Tokat Massif and Bakımlıdağ Complex. Tokat Massif is composed of low-grade metamorphic units (metabasite, marble, phyllite, serpentinite, micaschist, amphibolite and slightly blueschist). The Bakımlıdağ complex consists of an ophiolitic series consisting of basic ultra-basic gabbro, serpentinite and dolerite dykes. The basement units are unconformably overlain by Middle Late Eocene volcano sedimentary rocks. The unit is named Haydaroğlu Formation and is composed of alternation of conglomerate, andesitic-basaltic lava, tuff, agglomerate, volcanic breccia, mudstone, sandstone and shale. Quaternary alluviums are the youngest units in the region and cover other units unconformably. Agate formations are observed within the slope debris, volcanic breccias and volcanoclastic sandstones of the Volcano-sedimentary unit. In this region, there is a slip fault zone close to the WNW-ESE direction and inclined towards the north. Agates are concentrated on this zone. Agates are usually in the form of closed nodules (goid) in sizes of up to 25-30 cm with a few mm. Some of the small nodules are homogeneously composed of fire opals. Inside the nodules are filled with agate bands in different colours and patterns and there are mostly coarse crystal quartz in the middle. Mostly asymmetric gap fill structures are observed and red strips and yellowish green lace patterns in a thin agate sheath and the remaining space are filled with chalcedonies. Agate samples collected from the study area were classified in Selcuk University SÜKOP Gemstone Application and Research Center and then cleaned, cut, etched and polished for plate, ball and cabochon production. Rings, pendants, earrings, brooches, bracelets, rosary and keychains are made of polished products. Therefore, Almus agates can be used as gemstone with regard to structure-texture, hardness, variety of colours, polishing, light reflection, durability and wonderful patterns. In case of determination of the potential of agates in the region and evaluation of them with appropriate production methods without plundering, serious contribution can be made to the promotion and economy of the Almus region.eninfo:eu-repo/semantics/closedAccessTokat,Ornamental,SÜKOPAlmusAgatConference Object