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The current work investigates the impact of magmatic fluids and metasomatic processes on the Yolindi Cu-Fe skarn deposit in the Biga Peninsula, Turkey. It traces the stages of skarn evolution, from prograde to retrograde alterations, and investigates findings within a broader geological, mineralogical, and geochemical framework. Additionally, it assesses the evolutionary history of the Yolindi deposit in relation to calc-alkaline magmatic activity in an island-arc environment and compares its mineral compositions and genesis with other global and regional Cu-Fe skarn deposits. The Yolindi Cu-Fe skarn deposit in the Biga Peninsula was formed by the intrusion of Şaroluk quartz monzonite pluton into Upper Paleozoic Torasan Formation rocks such as phyllite, schists, hornfels, marble, and serpentinites. During skarnification, reactions between the magmatic fluids from the Şaroluk quartz monzonite pluton and the Torasan Formation produced skarn minerals associated with metals such as Fe and Cu. Initially, these reactions formed prograde skarn minerals such as augite-rich pyroxenes and andradite garnets with magnetite and pyrite. As the system cooled, these initial minerals underwent retrograde alteration, leading to the formation of minerals such as epidote, actinolite, and chlorite, as well as other copper and iron minerals including chalcopyrite, bornite, secondary magnetite, and specular hematite. Therefore, four main stages influenced the formation of the Yolindi Cu-Fe deposit: metamorphic bimetasomatic, prograde metasomatic, and retrograde metasomatic stages. Later, oxidation and weathering resulted in supergene minerals such as cerussite, malachite, and goethite, which serve as examples of the post-metamorphic stage. The mineralogical shifts, such as the andradite–grossular transition, reflect changing hydrothermal fluid compositions and characteristics due to the addition of meteoric fluids. Importantly, the formation of magnetite after garnet and clinopyroxene during the retrograde stage is evidenced by magnetite crystals within garnet. The mineral associations of the Yolindi Cu-Fe skarn deposit align with the global skarn deposits and specific Turkish skarns (e.g., Ayazmant Fe-Cu and Evciler Cu-Au skarn deposits). The Yolindi Cu-Fe skarn deposit, in association with ore-bearing solutions having magmatic origins, developed in an island-arc setting. [ABSTRACT FROM AUTHOR]

Twenty-eight copper-based artefacts, including unworked lumps, ornaments, and tools, recovered from PrePottery Neolithic B layers of Gre Fılla, located in the southeast of Anatolia, were analysed by hand-held, portable X-ray fluorescence spectrometer to understand the feasibility of instrument in identifying the type of copper minerals available at the settlement. The bulk analysis of eight lumps was further performed by inductively coupled plasma atomic emission spectroscopy and inductively coupled mass spectrometry. The results revealed important differences between the two approaches. According to the elemental composition obtained by bulk analysis, the lumps appeared to be malachite. The presence of lumps suggests that manufacturing of the objects was achieved at the site. The chisel axes, one with a bone handle, present the earliest examples of metal axes, although they reflect lithic manufacturing technology in contrast to postdated axes. A comparison with the contemporary settlement at Çayönü, Aşıklı, and Tel Halula reflects the model of copper metallurgy in the region at the beginning of pyrotechnology. [ABSTRACT FROM AUTHOR]

A common theory is that copper smelting first appeared in the Near East in close connection with the early pottery industry. However, copper smelting may well have been discovered many times in history and at many places. Our hypothesis is that copper smelting could have been discovered when the copper-bearing mineral malachite, accidentally or intentionally, was present in lime-burning kilns. To test our hypotheses, a series of test burnings during which malachite, limestone and solid carbon fuel were present in the same furnace have been carried out. The weight and copper content before and after burning was measured. The weight loss was the result of the evaporation of carbon-dioxide in the limestone and the evaporation of carbon-dioxide as well as water in the malachite. The weight loss and final copper content give a clear picture of the effectiveness of the burning procedure. The mechanism behind the successful smelting was most probably the reaction between the carbon in the solid fuel and the carbon-dioxide released from malachite and limestone when they were heated up. This reaction created the carbon oxide necessary for the reduction of "copper-oxides" to copper. The best conditions for discovering this conversion are likely to have existed in areas with an extensive production of lime plaster in combination with an abundance of native copper as well as malachite. The Anatolian mountains was one of the areas where these conditions were at hand. Massive lime production first began in this region in the PPNB around 10,800 BP. We, therefore, propose that copper smelting could have been discovered at this time in Anatolia. [ABSTRACT FROM AUTHOR]

In the vicinity of Yücepinar Village of Zile district of Tokat province, there are silicified wood formations in agglomerate levels in the Çekerek formation Middle Eocene aged. These formations consist of well— preserved tree trunks of about 1.5 m in diameter or branches and trunk parts in mm—1 m length. Generally, they are open-brownish cream; in some places they demonstrate dark brown, green, and blue colors. According to XRD and FT-IR analysis results of the samples, it is determined that the silicified wood formations are composed of quartz, cristobalite, malachite, azurite, hematite, graphite, and goethite minerals. According to XRF and ICP-MS analyzes of silicified woods, the high iron content (Fe2O3 8.29–63.79%) in the samples causes red brown color while the increase in copper content (Cu >10 000 ppm) causes blue and green colors. As a result of the cabochon cuts made from the silicified wood samples to be used for jewellery, products which have rich color composition and silky brilliance, keep the polish well and with high-strength are obtained. Particularly because of its color compositions, it is separated from similar silicified wood samples on the Earth. As a result of the surface studies carried out in the study area, it was observed that the silicified wood formations did not propagate much. In order to determine the reserves of these formations, which are thought to have significant economic value, it is necessary to carry out a more detailed exploration activity with trenching and drilling in the region. [ABSTRACT FROM AUTHOR]

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The Pınarbaşı porphyry Cu Mo mineralization is located at northwest of Gediz (Kütahya-Turkey) and east of Simav (Kütahya-Turkey) in western Anatolia. The Pınarbaşı Cu Mo mineralization is hosted by Pınarbaşı granitoidic intrusion consisting of granite, granodiorite and quartz monzonite. Geochemical and geochronological evidences for Pınarbaşı granitoidic rocks show that they are high-K calc-alkaline, and I-type granitoid magma likely developed post-collisional extensional regime. The U Pb zircon age of granite (18.88 ± 0.17 Ma) and quartz monzonite porphyry (18.27 ± 0.14) obtained from the Pınarbaşı granitoid show Early Miocene (Burdigalian). The Pınarbaşı Cu Mo mineralization predominantly comprises molybdenite, chalcopyrite, galena, sphalerite, pyrite, fahlore, magnetite, bornite, hematite, jarosite, malachite and orpiment occurred in disseminated form in veins/veinlets associated with potassic, phyllic (sericitic) and advanced argillic alteration zones. According to the paragenetic and crosscutting relationships of veins/veinlets, the ore-forming process were divided into three stages; early-stage: quartz – molybdenite ± K-feldspar ± pyrite veins associated with potassic alteration, middle-stage: quartz ± calcite ± chalcopyrite ± galena ± sphalerite ± molybdenite + pyrite veins in phyllic alteration and late-stage: quartz ± calcite ± pyrite veins associated with advanced argillic alteration. Three types of fluid inclusions in quartz distinguished were designated as L-rich L + V phases (Type-I), salt-bearing L + V + S (Type-II), and V-rich L + V phases (Type-III). FIs of the early and middle stages are predominantly Type-II and Type-III inclusions, whereas the late-stage minerals commonly contain Type-I inclusions. Homogenization temperatures and salinities of FIs trapped in the early-stage quartz range from 481 to 590 °C and 13.19 to 61.1 wt% NaCl equivalent, respectively. FIs in quartz of the middle-stage yield homogenization temperatures (Th) of 310 to 460 °C, while halite dissolution temperatures are ranged from 264 to 430 °C, and salinities of 7.9 to 50.3 wt% NaCl eq. Homogenization temperatures and salinities of FIs in calcite of the middle-stage are range from 270 to 420 °C, 3.4 to 49.1 wt% NaCl eq. The late-stage homogenize at temperatures of 138 to 240 °C, and salinities of 0.9 to 6.5 wt% NaCl eq. The δ34S H2S values (0.6 to 4.5‰) of sulfides (molybdenite, chalcopyrite, pyrite and galena) and the δ18O SMOW (6.9 to 9.6‰) - δD (−71 to −86‰) values of molybdenite-bearing quartz from Pınarbaşı Cu Mo mineralization suggest a magmatic origin for the ore-forming fluids. The δ13C PDB (from −4.65‰ to 0.55‰) and δ18O SMOW (from 9.05‰ to 18.76‰) values of calcite which is one of the most common gangue minerals in Pınarbaşı mineralization show a high temperature influence and/or sedimentary contamination process to magmatic carbonate as well as continental carbonate. The S–O–H–C and U Pb isotopic compositions indicate that the metallic elements and fluids came primarily from a magmatic source linked to Miocene intrusion. The geological, geochronological, and geochemical data support a magmatic-hydrothermal origin for the Pınarbaşı Cu Mo mineralization and confirm that mineralization is formed from an Early Miocene porphyry-related magmatic-hydrothermal system that is genetically linked with Eğrigöz and Pınarbaşı granitoids. • Granitoid-hosted Pınarbaşı Cu-Mo mineralization is located in the western Anatolia known as an economically important metallogenic province. • Stable isotopic data provide evidence of the ore-forming fluids came primarily from a magmatic source. • The Pınarbaşı granitoid were formed with an emplacement age of 18.88±0.17 Ma (granite) and 18.27±0.14 Ma (quartz monzonite porphyry). • Contemporaneous porphyry-style mineralization and Pınarbaşı intrusion were emplaced during the Early Miocene (18.3 Ma). [ABSTRACT FROM AUTHOR]

We used a fast method to interpret self-potential data: the depth from extreme points (DEXP) method. This is an imaging method transforming self-potential data, or their derivatives, into a quantity proportional to the source distribution. It is based on upward continuing of the field to a number of altitudes and then multiplying the continued data with a scaling law of those altitudes. The scaling law is in the form of a power law of the altitudes, with an exponent equal to half of the structural index, a source parameter related to the type of source. The method is auto-consistent because the structural index is basically determined by analyzing the scaling function, which is defined as the derivative of the logarithm of the sell-potential (or of its pth derivative) with respect to the logarithm of the altitudes. So, the DEXP method does not need a priori information on the self-potential sources and yields effective information about their depth and shape/ typology. Important features of the DEXP method are its high-resolution power and stability, resulting from the combined effect of a stable operator (upward continuation) and a high-order differentiation operator. We tested how to estimate the depth to the source in two ways: (1) at the positions of the extreme points in the DEXP transformed map and (2) at the intersection of the lines of the absolute values of the potential or of its derivative (geometrical method). The method was demonstrated using synthetic data of isolated sources and using a multisource model. The method is particularly suited to handle noisy data, because it is stable even using high-order derivatives of the self-potential. We discussed some real data sets: Malachite Mine, Colorado (USA), the Sariyer area (Turkey), and the Bender area (India). The estimated depths and structural indices agree well with the known information. [ABSTRACT FROM AUTHOR]