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Regarding the growing uses of the nanoclay for different applications nanoclay characterization has become highly important. However, there is not enough information about a developed characterization methodology of nanoclay materials. In this study the montmorillonite was purified using different physical or chemical methods and the purity of montmorillonite in the nanoclay samples were characterized using different methods such as XRD, SEM/EDX, FTIR, TG/DTA, and CEC. Results indicated that parallel comparison of results of different characterization methods would provide important information about the type of clay mineral, type of non-clay mineral in the samples, semi-quantification of minerals in produced nanoclay, and change in the nanometric characteristics of the nanoclay. Combination of XRD and SEM/EDX results provided interesting information about the amount of impurities in the nanoclay samples in addition to their structural morphology. Comparison of the CEC with the XRD results of the treated nanoclay samples provided information about type of clay in the nanoclay samples. And finally combination of XRD and TG results provided information about the type of other clay minerals (non-montmorillonite ones) in addition to existence of organic impurities in the nanoclay samples.

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Kaolin deposits in the Nivasht and Kabudkamar areas are located in ~25 km northwest of Saveh, Central province. Field observations along with petrographic examinations revealed that genetically these deposits are alteration products of igneous rocks such as andesi-basalt, trachy-andesite, and andesitic tuff of upper Eocene age. In this study, the physical, chemical, and mineralogical properties of the kaolin deposits in Nivasht and Kabudkamar were investigated on the basis of industrial applications. Based upon mineralogical data, the principal constituent minerals in both deposits are quartz, kaolinite, halloysite, muscovite-illite, Montmorillonite, pyrophyllite, plagioclase, hematite, goethite, anatase, akermanite, alunite and/ or natroalunite, and talc. Further investigations in the studied areas showed that the kaolinitic clays have mostly firing color within the range of milky white to dark gray. Consideration of parameters such as capability of water absorption, resistance in dry state, firing contraction, low thermal efficiency, and the values of major oxides demonstrated that the kaolins at Nivasht and Kabudkamar possess suitable standard conditions for application in ceramic (for floor and wall) industries, however, their application in other industries requires further processing.

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The Rahmatabad Kaolin deposit is located about 25 km southwest of Nain. This deposit is formed by alteration process from Eocene volcanic rocks and pyroclastic units. Mineralogical studies display that the kaolinite, jarosite, hematite, quartz, calcite, anortite, alunite, diaspore, chlorite, montmorillonite, illite, albite, orthoclase, halite, sanidine, goethite, malachite, azurite and sericite are the rock-forming minerals in this deposit. Based on geothrmometry data on the chlorite which produced by alteration process, the temperature of hydrothermal fluid formed this deposit has been between 98.25 ^oc to 321.04^oc. According to geochemical studies, the alteration process of volcanic and pyroclastic rocks to Kaolin have been accompanied by enrichment of Rb, Cs, Ba, Sr, Nb, Hf, Zr, Y, Th, Al and U; leaching-fixation of Si, Ca, Ti, Na and P; and depletion of Fe, Mn, Mg, K Cr, Ni and RREs. Furthermore, the geochemical data can be refer to high (La/Lu)_N, and high Sr, Ba values than to La, Ce and Y. Also Ce and Eu anomalies in the studied area were controlled by degree of feldspar alteration as well as changing the in degree of oxidation of environment respectively.  It seems that the development of the Rahmatabad Kaolin deposit was supported by mixing of two hypogene and supergene processes. The discrepancy in the rate of alteration intensity of the source materials, chemistry of altering solutions, adsorption, incorporation in crystal lattice, difference in degree of complexation with sulfate, chloride, and fluoride ligands and difference in the stability scale of primary minerals against the alteration are considered as six important factors for controlling the mobilization, distribution, and concentration of elements in the Rahmatabad Kaolin deposit. 

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Natanz, 1:100000 geological map, is located in northeast Isfahan, in the Urumieh-Dokhtar structural zone. This sheet is a prospective area for Cu, Zn and Pb mineralization. Spatial distribution of geochemical anomalies for mineralization was identified; using  pathfinder elements statistic method. The sample from catchment basin technique was applied on stream data. Then threshold elements were recognized and separated anomalies. The results show a good distribution of Pb, Zn, As and Sb elements close to copper index in the Natanz map. Moreover, fractal model used to introduce new anomalies in south portion of map for future exploration prospecting.  

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Ahar area is a part of the Arasbaran metallogenic zone in northwestern Iran, where numerous hydrothermal Cu-Au deposits have been formed. In this regard, Safikhanlu, Niaz, Mazraeh, Anjerd and Kujanagh deposits, as representative deposits, have been observed and structural measurements were performed in the field. In this area, Cretaceous limestones along with volcanic rocks are exposed as the oldest rocks in the region along with Eocene latite-andesites. These volcanic rocks have been intruded by Oligocene plutons such as Safi Khanlu with the combination of granite-quartz monzonite and Khan Kandi with the combination of Monzonite-Gabbro, causing phyllite, argillic and siliceous alterations in Safi Khanlu, extensive argillic alteration in Kujanagh and potassic in the Niaz  area. With a time interval, magmatic activity in the Late Miocene-Pliocene resumed and caused phyllic and propylitic alteration in the Mazraeh and argillic, phyllic, propylitic and potassic in Anjerd area. These alterations were studied using ASTER satellite images and PCA and SAM methods. Then, with field studies, the trend of major fractures in each of the mentioned deposits was determined and compared with the results obtained from remote sensing. The structural analysis showed that the predominant trend of mineralization and alteration zones in the studied deposits is northeast-southwest and is consistent with the predominant trend of the fault lines extracted from satellite images. Based on these results, it can be concluded that fault and fracture have played a major role in controlling and forming gold and copper reserves in the Ahar region.

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The Kamar-Gov study district is located south of Hashtjin city in the Ardabil Province (NW Iran). The geological units in this district include lavas (with composition of basaltic trachy-andesite to rhyolite), sub-volcanic rocks (as dyke and stock with composition of porphyritic trachy-andesite and trachyte) and crystal, vitric (lithic) tuffs (intermediate and felsic composition). Extensive zones of silicic, sericitic-argillic, advanced-argillic, and chloritic alteration have formed in these rocks. Pyrite is the prevalent metal mineral in the study area and approximately extended in all rock units. Besides pyrite, chalcopyrite, chalcocite, galena, sphalerite, hematite, and magnetite are also present. Covellite, digenite, and goethite are supergene minerals. Ore minerals have formed in crystal, vitric tuff and rhyolite as veinlet, dissemination, strata-bound dissemination, and inside silicic veins/veinlets. Three types of primary fluid inclusions are present within quartz minerals of silicic veins/veinlets and accompanied by disseminated ore minerals, including liquid-rich two phases, vapor-rich two-phases, and salt-saturated three-phase fluid inclusions (liquid, vapor, and halite + sylvite). Micro-thermometric analysis of these fluid inclusions shows the salinity of 1.05-14 wt% NaCl equivalents with the highest frequency of homogenization temperatures between 200 and 300 °C. The ore formation type is similar to intermediate sulfidation epithermal deposits, based on features like the vein-veinlet shape of ore mineralization, colloform and crustiform textures, base metal mineralization, the mineral assemblage of kaolinite – muscovite – pyrite ± sphalerite, intermediate salinity and temperature of the fluid, and probable effect of the boiling process.
 

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   Makran amphibolites are exposed in different locations in the northern Makran ophiolitic belt. Based on lithological studies and mineral assemblages in these rocks, they are containing ordinary amphibolite (oriented and massive), garnet-pyroxene amphibolite, epidote-garnet amphibolite and marble. The minerals that made up ordinary amphibolites (oriented and massive) include amphibole, plagioclase, zircon apatite, quartz and sphene. In addition to these minerals, garnet and pyroxene are found in garnet-pyroxene amphibolites. In addition, epidote, garnet and pyroxene are found in epidote-garnet amphibolites. Also, marbles are containing calcite with a distinct cleavage, quartz and amphibole. Geochemistry of amphibolites shows that these amphibolites are of igneous origin with basaltic protolith that originate from an enriched mantle. Amphibolite samples of the region have relatively similar composition based on the diagrams of changes of normalized rare earth elements to chondrite and N-MORB and are also similar to mid-oceanic ridge basalts (MORB) as well as within plate volcanic zone (WPVZ) basalts in terms of geochemical properties.

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The Balestan iron deposit is located about 55 km southeast of Urmia city. The main host rock is the quartz sericite schist unit of the Early Precambrian age. Major mineralization occurred along the schistocytes of the host rock. However, open space filling structure is also abundantly observed in the fault zones. Based on field evidence and microscopic studies, the dominant iron mineralization is in the form of magnetite, which is observed along with pyrite and chalcopyrite. Geochemical investigations revealed that the distribution patterns of trace elements and major oxides are very similar to other hydrothermal iron deposits. The microthermometric studies of fluid inclusions shows an average homogenization temperature and salinity of about 276°C and 7.3 wt% NaCl equivalent, respectively.The variation trends in salinity and T_h of fluid inclusions can be explained by a cooling and pressurization of ore-bearing fluids. Also, these data show that the Balestan iron ore deposit is located within the field of mesothermal ore deposits.

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    The study amphibolites are located in Hashtbandi village (east of Minab). The Makran amphibolites form a part of the metamorphic rocks of northern Makran ophiolitic belt, which are found in massive and orientated forms. Based on the indicator minerals, these rocks include ordinary amphibolite, epidote-garnet amphibolite and garnet-pyroxene amphibolite. The minerals in the ordinary amphibolites include amphibole, plagioclase, zircon apatite, quartz and sphene. In addition to these minerals, garnet and pyroxene are found in the garnet-pyroxene amphibolites, and epidote, garnet and pyroxene in the epidote-garnet amphibolites. Amphiboles in these rocks are calcic type and composition from magnesian to ferrohornblende. The clinopyroxene is calcic type and mostly in the diopside range. Garnets have a compositional range from almandine to grossular, and the trend of changes in composition and elements such Mn, Mg, Ca and Fe²⁺ from the rim to core in this mineral does not show a specific trend and is linear. The lack of clear zoning of elements such Mn, Mg, Ca and Fe²⁺ and their flat patterns in garnet indicate rapid diffusion during progressive metamorphism and at temperatures above 600 °C. The composition of plagioclases is mostly in the albite- labradorite range. The sphene is in the metamorphic/hydrothermal range, and epidote is classified in the epidote subgroup. The hornblende-plagioclase geothermometery and Al-in-hornblende geobarometery result 590 – 690 ºC and 5.5 – 7.9 kbar P for the oriented amphibolites and 550 to 720 ºC and 4–6 kbar for the massive ones. A P-T phase diagram shows that the amphibole + plagioclase + epidote+ sphene assemblage is stable at 450 – 650 ºC T and < 8 kbar P corresponding to the hornblende – plagioclase thermobarometry results. In higher temperatures and pressures, clinopyroxene and garnet occur in the assemblages, respectively. On this basis, the garnet + pyroxene bearing amphibolites endured higher metamorphism degrees, at comparative temperature and pressure of > 650 ºC and > 8 kbar.