مجله بلور شناسی و کانی شناسی ایران
سال سی‌ام شماره 3 (پیاپی 89، پاییز 1401)

Ghorban polymetallic deposit is located in the Torud-Chahshirin Range, at the northeast end of Cheshmeh Hafez mining district in the northern margin of the Central Iran geotectonic zone. The bed rocks of the area consist mainly of volcanic to sub-volcanic of Middle to Upper Miocene in age, such as basalt, andesite-basalt, andesite, trachy-andesite, tuff, agglomerate, and breccia tuff. These rocks have been pervasively altered by hydrothermal fluids. Alterations include propylitic, sericitization, chloritization, argillic and silicification. Mineralization occurred in both hypogene and supergene zones of the area. Geochemical studies show that Cu has a very low correlation with Zn and Pb and a positive correlation with Ag. Au also has the highest correlation with Ni. Fluid inclusions have been done in a quartz samples as well as one calcite sample which are associated with ore minerals. Fluid inclusions at room temperature are liquid-rich bi-phasic type. Most of them are made up of liquid fluid only and a few of them are made up of liquid fluid with vapor bubble. Homogenization temperature and salinity in the samples are between 112-254 ℃ and 0.88- 18.22 wt% NaCl equivalents. The homogenization temperature and fluid salinity data shows that mineralization has taken place due to injection of several phases of high saline fluid and mixing with low saline fluid and was diluted during the cooling. Mineralogical, geochemical and fluid inclusions data show that the Ghorban pollymetals deposit is epithermal deposits.

The present study focuses on the geochemistry and genesis of REE minerals in the Tang-e Pirzal karst bauxite deposit. The deposit is located about 45 km east of Dehdasht city in the central part of the Zagros Fold Belt. The ore bodies comprise a series of contiguous lenses that occur as infills of deep karst cavities, depressions, and fractures within the upper neritic carbonates of the Cenomanian–Turonian Sarvak Formation and are structurally controlled by strike-slip fault systems. The most frequent authigenic REE minerals are fluorocarbonates of bastnäsite group that form a solid solution series between end members parisite (CaCe2(CO3)3F2) and bastnasite (CeCO3F). The formation of bastnasite-Ce and parisite-Ce suggests that cerium as fluoride and/or carbonate–fluoride complexes were simply leached by acidic downward solutions and finally precipitated on the geochemical barrier of the carbonate bedrock under alkaline and reducing conditions. Cerianite (CeO2) occurs mainly as fine grains in the porous aggregates of the cryptocrystalline matrix. Cerianite precipitation may occur due to the predominance of acidic/oxide conditions in the upper parts of the bauxite profile. Examination of the vertical distribution of the ∑REE, (La/Yb)N, Ce/Ce*, and Eu/Eu* indexes indicates progressive enrichment of the REE and slight LREE/HREE fractionation toward the lower parts of the bauxite profile. Cerium behaves differently from the other REEs and shows fluctuating behavior throughout the Tang-e Pirzal profile, which can be related to periodical fluctuations of the groundwater table in response to environmental changes.

Sabalan is a young member of the Sanuzui volcanic assemblages, belonging to the Alborz Magmatic Arc (AMA(. In Sabalan mountain range, a series of volcanic rocks with a combination of andesite, basaltic andesite, rhyodacite and trachyandesite are present. The  texture of these rocks is often porphyritic with microlithic paste, porous porphyritic and sometimes glomeroporphyria, sieve and trachyte. Major minerals include clinopyroxene, plagioclase, and one or more mafic minerals such as hornblende and pyroxene. Secondary minerals include opaque minerals, iddensite, biotite, chlorite and calcite. Investigation of mineral chemistry of basaltic rocks in the region shows that the composition of calcium plagioclase crystals is moderate (An72-93(. Based on temperature–barometric diagrams of plagioclase and amphibole, a temperature of 540 to 750 oC and pressure of 5.30 to 7k have been calculated, which corresponds to the depth of the middle to lower crust. Mineralogical studies and whole rock geochemical analysis show that these rocks formed in a tensile and intercontinental zone.

Hormuz and Gachin salt domes are located on the Zagros Belt, about 17 km south and 50 km west of Bandar Abbas, respectively. Extensive outcrops of rhyolite and tuffs are observed in these salt domes. The main constituent minerals of rhyolite include hematite, magnetite, pyrite, chalcopyrite and apatite (Hormuz salt dome). Geochemical evidence indicates that the rhyolite of the Hormuz and Gachin domes belongs to the calc-alkaline to shoshonitic of magmatic series and formed during a tectonic regime of active continental margin volcanic arcs. Absence of negative Nb anomaly and positive anomaly of Pb in Hormuz and Gachin rhyolites indicate magma derived from the mantle source with low contamination from crustal rocks and subduction-dependent. The average ​​of (La/Yb)N and (Ce/Yb)N ratios as index (LREE/HREE) indicate high enrichment of LREE against HREE for Hormuz rhyolite versus Gachin rhyolite,. Strong and positive correlation between ΣREE with Fe, P and Ca oxides as well as positive La and Ce anomalies and negative P anomaly in Hormuz rhyolite samples compared to Gachin samples, are consequence of the presence of apatite mineral in these rocks. The distribution pattern of Light Rare Earth Elements in Hormuz salt dome apatites show a more regular and uniform trend. Thus (LREE) show more adaptation to focus on apatite minerals. The low ratios of Eu/Eu* in apatites of Hormuz (0.01-1.04 ppm) rather than ryholites of Gachin (0.1-3.1 ppm) shows changes in the magma composition during the formation of apatites. In addition, increases in negative Eu anomaly can be due to the crystallization of feldspars that separate Eu from the melt and its concentration; therefore, the Hormuz apatites indicates a high degree of differentiation. In Hormuz salt dome apatites, enrichment of LREE to HREE, negative Eu and positive Ce anomalies and significant ΣREE concentrations up to 8882 ppm as the indicator mineral plays an important role in evaluating the distribution of rare earth elements in the rhyolite of the Hormuz salt dome.

Deh-Zaman mylonitic granite is located northwest of the Lut Block (Kashmar-Kerman zone) in the northeastern part of Kuh-e-Sarhangi shear zone. In this granitic body (~557-561 Ma), mylonitic foliation with S62˚E/80NE attitude is very well developed. The mean pitch of stretching lineation is ~40 ˚ toward the southeast. The main purpose of this study is to quantify the vorticity number based on the strain of feldspar crystals. The microstructural evidence of the feldspar crystals indicates that the sense of shear is left-lateral strike-slip in the region. The presence of moderately euheadral porphyroclasts of feldspar with observed dynamic recrystallization of grain boundary migration type, indicates ~450°C deformation temperature that shows a low to medium grade mylonite. The vorticity number of this mylonite granite is estimated to be 0.8 based on the feldspar crystal strain. This indicates the predominance of simple shear component (60%) over pure shear (40%) and the development of mylonitic structure under transpression conditions.

The Khakoo deposit is located in south and southeast of Hamedan city, near the Khakoo village, in western Iran. In this area, blue corundum formed inside the pegmatite veins and granite body. Geochronological data, using various radiometric methods, show that metamorphic rocks formed during the Jurassic to Cretaceous. Then during the Middle Jurassic to Early Cretaceous time, a massive intrusive masses as well as younger phases and pegmatite vines penetrated into this body. The hydrothermal activity of hot fluids driving from the granite mass has created specific paragenesis including corundum crystals. Aluminosilicate and corundum minerals are formed in the pegmatite filons and the margin of granite body. Based on recent studies, the metamorphic–metasomatic process and per-alumnus alkaline composition of intrusive body made a genetic model which based on the bimodal exchange of hot fluids at high temperature and medium pressure are the phenomenon of extensive desilicification and increases of the Al/Si ratio. Metasomatic progressive processes have changed aluminosilicate and plagioclase minerals to corundum in an open geochemical system. Therefore, the Khakoo deposit in a metasomatic magmatic model can be justified. According to the results obtained in this study, natural corundums have a large variation in most trace elements. The collected crystals are in the 6th- 7th rank in terms of tone, from the Saturation terms in the range of 2 and 3 cool colors and based on the Hue termsour samples fill in the Violet Blue (VB) and Blue (B) groups. The Khakoo corundum deposit contain less than 1% (Wt) Iron, 10 to 47 (ppm) Gallium, 83 to 690 (ppm) Titanium, and 30 (ppm) Vanadium. Finally, the Khakoo deposit has resembled associated deposits with the alkaline syenite in Tanzania mines.

The Ghoochi area is a part of volcanic-plutonic zone of the Lut block and is located in eastern Bajestan city in the Razavi Khorasan Province. The geology of the area includes Jurassic metamorphic (slate and metasandstone), Early Cretaceous sedimentary (limstone, conglomerate and sandstone) and Late Cretaceous subvolcanic (pyroxene diorite porphyry) rocks. Mineralization is formed along faults with northwest-southeast and east-west trends in the reduced pyroxene diorite porphyry host rock (Late Cretaceous). Hypogene minerals are pyrite, sphalerite, galena, pyrrhotite, arsenopyrite, chalcopyrite, calcite and quartz with lesser amounts of chlorite. Mineralization is seen along with the structures and textures of vein-veinlet, open space filling, disseminated, replacement and exsolution. Main alterations consist of propylitic-sericitic, sericitic-carbonate-silicification and carbonate-silicification±chlorite. Maximum geochemical anomalies observed include for gold with 2639 ppb, arsenic 11065 ppm, lead 45400 ppm, zinc 19400 ppm, silver 12 ppm, and copper 725 ppm. Based on geology, alteration, mineralogy, texture and geochemistical studies, Ghoochi area can be probably classified in reduced-intrusion related gold systems (RIRGS).

Qarah Gol area is located in Ahar-Arasbaran metallurgical zone in Ardabil Province, Meshkinshahr city in Moradloo section. The oldest rock units in the study area are related to the Cenozoic (Eocene), which consists of volcanic breccia. In this area, microquartzdiorite have penetrated into volcanic and pyroclastic rocks and alteration and mineralization have taken place on a weak scale. The results of Aster image processing, using absorption bands and selection of the best ratio color composite (5 + 7.6, 9.8, 4.5) respectively for the detection of argillic, phyllic and propylitic alterations, as well as using techniques such as principal component analysis and spectral angle mapping indicate that associated alterations in the central part of this deposit is consistent with petrographic studies in Qarah Gol area. Field studies have shown that the results of Spectral Angle Mapper (SAM) have performed better than the principal component analysis (PCA) in the detection of alterations.

Chah Mikh area is a part of Lout blocks in 115 kilometers south west of Birjand. Stones in the studied district are Andesite, pyroxene – Andesite, Porphyry Diorite, Hornblende Andesite, Hornblende-Pyroxene, Monzodiorite , and Basalt. The texture of the most masses is Porphyritic. In central part of the studied area there are many extensive alteration zones which are directly related to semi-deep masses. Richness of light rare earth element, partial emptiness of heavy rare earth elements and the negative anomaly are their specialities and it represents Metalumina Magmatism types 1 in the active border of the continent and volcanic plates. Mineralization in this area in silic beefs arises from the action of the semi-deep stock. In terms of mineralogy original sulfide mineral existed in the area are Pyrite generation 1 Pyrite generation 2, Chalcopyrite, Chalcocite, Covellite and among the oxide phase mineral: Malachite Azurite, Chyrsocolla, Hematite and Goethite can be mentioned.

The Gheshlagh Cu-deposit is located in the Tarom-Hashtjin metallogenic belt (THMB) of northwest Iran. The mineralization is hosted by Eocene volcanic and volcaniclastic rocks of the Karaj Formation at the subduction-related magmatic arc setting. The geochemistry and petrogenesis analysis confirmed the subduction setting and mineralogically- dominant plagioclase-pyroxene compositions of the host rocks. A good correlation between Al, Fe, Ca, Mg attests to the minerallogic composition, also a strong correlation between chalcophile elements like Pb, Zn, S, Cu and Ag shows sulfide mineralization in the rocks. Based on cross-cutting, the relationship of vein, textural relationship, mineral assemblage and fluid inclusion microthermometry show that alteration and mineralization in the Gheshlagh ore deposit occurred in the fourth main stages. The first stage (stage I) is accompanied by the propyllitic alteration and formation of pyrite (discontinuous) under reducing conditions in the seafloor and very shallow burial environment. The alteration is attributed to magmatic and seawater mixing, which with assuming of the δ18O ranges from 6-10 ‰ for the magmatic fluids and -0.8 to -0.9 ‰ for the Eocene seawater, supported by the values of δ18O quartz (2.1-6.5 ‰) corrected by homogenization temperature of 389 ºC of the related rocks. As the depth of burial increases (stage II), sediments have hardened and also tectonic and lithostatic stress, dykes and floods cause intraformational and magmatic fluids circulation by compaction and heat recharging. These high-temperature fluids are enriched in copper during circulation among volcanic units. Copper-rich fluids migrate upward and are reduced by entering the pyrite-rich andesitic-basaltic unit, and copper is deposited in sulfide forms such as chalcopyrite and chalcocite in the favorable sites. In deeper burial (stage III), the copper mineral formed in the previous stage would be replaced by bornite and digenite. At the supergene condition (stage IV), due to oxidizing conditions, weathering, and leaching, copper sulfides mostly appear as malachite in the joints and voids. According to the results, the mineralization model of the copper in the Qeshlaq deposit can be considered as manto type.

There is a growing interest in the synthesis and applications of cobalt oxide nanoparticles due to their unique properties. Current methods in nanotechnology focus on developing a new technique for the synthesis of nanoparticles using biological methods such as using plant extracts, mucilage, essential oils, fungi, or bacteria that can minimize the use of hazardous substances. Therefore, in this study, the synthesis of cobalt oxide nanoparticles is provided in a simple green and environmental friendly method using Cydonia oblonga seed mucilage as a reducing and stabilizing agent and cobalt (II) nitrate hexahydrate as a precursor of cobalt at different temperatures of 500, 600, 700 and 800°. Prepared nanoparticles were investigated using X-ray diffraction (XRD) techniques, Fourier transforms infrared spectroscopy (FT-IR), Ultraviolet-Visible (UV-Visible) spectroscopy, and field emission scanning electron microscopy (FESEM). XRD showed the formation of the cubic phase cobalt oxide nanoparticles with an average particle size of 31 to 63 nm, and the size of cobalt oxide nanoparticles increased with the calcination temperature. The FT-IR showed a strong absorption band related to the stretching vibration of Co3+-O and Co2+-O bond and confirmed the formation of Co3O4 structure in all samples. The results of the UV-Visible spectrum of the samples showed the band gap value of the nanoparticles in the range of 3.64 – 3.93 eV. Using FESEM images, it can be seen that the particles have a spherical shape.
 

In this paper, the nanoparticles of FeNi3 were prepared by hydrothermal and co-precipitation methods. Also, different times and temperatures with different amounts of the hydrazine reducing hydrate were investigated in hydrothermal method. After fabrication of the samples by two methods, the samples have been characterized using the x-ray diffraction analysis (XRD), the field emission scanning electron microscopy (FESEM), and magnetic properties of the samples using a vibrating sample magnetometer (VSM). The results of diffraction pattern show that the amount of hydrazine hydrate used is very effective in single-phase sampling. FESEM images show nanoparticles, but at some temperatures and times, particles are not formed or stickiness and melting are observed. The results of VSM analysis show that the samples have high magnetic properties in both methods and not much change in saturation magnetization between samples was seen in both methods.

In this research, titanium dioxide (TiO2), as a metal-oxide semiconductor that can be applied in dye-sensitized solar cells as a photoanode, was studied and synthesized. For this reason, thin films of TiO2 were grown using the spray pyrolysis method and their physical properties were studied. To prepare the FTO substrate as the conductive layer, the FTO layer was deposited on the glass substrate. The transmittance above 90% in the visible region and low electrical resistance allows the use of the synthesized FTO as a transparent electrode. Subsequently, TiO2 films were coated using spray pyrolysis at the temperature of 150°C on top of both bare glass and FTO coated glass substrates. The precursor solution for spray was made of TTIP as the main material and isopropanol as solvent. Samples were prepared by two methods of pulsed and non-pulsed spraying in two volumes of precursor solution of 200 and 350 mL. Results showed that the pulsed deposited samples cause the formation of TiO2 films with higher crystal quality. XRD pattern analysis revealed the formation of the anatase crystal phase with preferred growth along the (101) plane on the FTO substrate. Considering its physical characteristics, the TiO2 sample deposited on FTO in a precursor solution volume of 200 mL by the pulsed method was introduced as the most suitable sample for being used as a photoanode.

In this research, nanocrystals of metal-organic frameworks (MOF), based on metal ions of aluminum, bismuth, cobalt, chromium, copper, tin, titanium and zinc with homogenous morphology were synthesized using a solvo-thermal method as an organic framework to form the porous MOF-doped TiO2 for electron transport layer in perovskite solar cells. By thermally decomposing the MOF-doped TiO2 layer in air, the organic template was removed, and porous MOF-doped TiO2 was obtained.  The results of optical properties of crystal structure of porous MOF-doped TiO2 layer showed that doping with MOF remarkably improved the absorption ability of TiO2-MOF layer toward the Uv-Vis region with band gap energy less than of 2.7 eV.  The photoluminescence spectroscopy was conducted to illustrate the improvement of electron transfer in the doped material further. The power conversion efficiency of solar cells using MOF-doped TiO2 was found to improve in comparing that of solar cells using pristine mp-TiO2.