مجله بلور شناسی و کانی شناسی ایران
سال بیست و ششم شماره 4 (پیاپی 74، زمستان 1397)

The Golgohar iron mine is located about 55 km southwest of Sirjan in the Sanandaj-Sirjan structural zone. We distinguished five mineralization zones, on the bases of mineral assemblage with magnetite. The gangue minerals are pyrite, pyrrhotite, chalcopyrite, siderite, apatite, serpentine, talc, chlorite, amphibole, calcite, dolomite and quartz. All chlorites are tri-octahedral in nature. The chlorites in MPPC and MTCA are pennine and pennine-clinochlore, respectively. The chlorites in chlorite schists have wider compositional range from pennine, clinochlore, pycnochlorite to ripidolite. Chlorite in mica schists and hornblendite are ripidolite. The chlorites with the highest amount of Mg have formed from mineralizing fluid. With decreasing of fluid/rock ratio, the chlorites show trends of decreasing Mg and increasing Fe and AlIV. Increasing of the Mg/(Mg+Fe) ratios from host rock to mineralization zones are different to those from the iron formaion. The content of minor elements in the structure of chlorite depends on the fluid composition, other crystallized minerals from the fluid, water/rock ratio and the composition of host rocks. The chlorite formation temperatures are ranging between 245°C and 415°C. MPPC zone have the lowest temperature (avg = 301°C), so Mg-rich chlorites are formed at lower temperature rather than Fe-rich Chlorites.

The Bozjani copper deposit is located about 30 km west of Fariman city, Khorasan Razavi Province. Host rocks to mineralization are mostly pridotites and basalts of Fariman ophiolitic sequence. Ore body consists of two parts: lower and upper. Lower part has formed a stringer of primary sulfides as stockwork, veinlets, and disseminated. Uppermost part has lenticular shaped dominated by ribbon-like, fine grain and rounded primary sulfides. Mineralogical investigations show pyrite, marcasite, chalcopyrite, bornite, sphalerite, galena, native copper, and magnetite are primary minerals of ore body associated with secondary minerals as coprite, tenorite, covellite, chalcocite, chrysocolla, malachite, azurite, jarosite, limonite, and hematite. According to geochemistry of immobile elements, the host mafic rocks fall in boninite tectonic setting. Mass balance calculations show enrichments of Cu, Pb, Th, As, Ag, Tl and U during evolution of Bozjani copper deposit. The results of host rock, structure, texture, mineralogy and geochemistry in this research reveal that Bozjani deposit resemble volcanic massive sulfide deposit dominated by mafic rocks. Evolution of this deposit is related to four stages including hydrothermaly alteration, seafloor weathering, regional metamorphic and weathering of terrestrial.

Dioritic plutons and pinkish alkali-feldspar granitic dikes of Kalateh area (northwest of Khur city) intruded in Neoproterozoic basemental of Jandagh- Arousan complex. Field observations, petrography and geochemical studies indicate that these intrusive rocks have I-type nature and belong to medium-high K calc-alkaline granitiods and also have genetically relationship with each other. Their parental magmas produced by partial melting of metasomatized mantle wedge which was located above the subducted Neotethyan oceanic slab. The mentioned magmas generated in an intracontinental back arc extensional setting in relation to the subduction of oceanic Neotethys slab. U-Pb dating results on separated zircon from dioritic and alkali-feldspar granitic rocks indicated 213.9 ± 1.6 to 221.16 ± 1.6 Ma interval age (corresponding to Late Triassic). These igneous rocks are indications of magmatic manifestations of Early Cimmerian Orogeny.

Jaghin ophiolite rocks are located in the east of Hormozgan Province and southeast of Rudan city in the ‎direction of the Makran zone. Lithologically, ultrabasic rocks such as dunite and harzburgite, and basic magma, including gabbro-norite and basalt, have been identified. According to chemical crystal analysis, the composition of pyroxenes in basic (Gabbro-norite) rocks is more than iron and magnesium, and poor of sodium, which included clinopyroxen with diopside and sometimes augite composition, as well as orthopyroxene is more than bronzite composition. Plagioclase crystals present in gabbro-norite rocks, also divide into high-sodium and medium-calcium types, which have mostly composition between albite and bitonite. Due to the thermometric of these masses and the utilize of the two-pyroxene method, the ‎temperature of forming these masses is determined to be 800-1200 °C and‎, also using the barometric of aluminum distribution in pyroxenes, the pressure on the clinopyroxenes formation estimated to be about 6-12 kbars.

Gushfil deposit is located SW Isfahan within Malayer-Isfahan Metallogenic Zone. Mineralization occurs at contact of Jurassic shale and Cretaceous dolomite as epigenetic with structural control. Paragenetic minerals are sphalerite, galena, and pyrite associated with dolomite, quartz, organic matter, and minor barite as gangue minerals. These minerals show berrecia, veinlets, open space filling, and dessiminated textures. Dolomitization and silicification are the most important alteration zones. Ore chemistry indicates galena is Ag and Sb-rich and Bi-poor. Sb/Bi ratio in galena is up to 14, which is indicator of low temperature deposits. Sphalerites are Fe and Cd-rich type. Based on fluid inclusion studies, formation temperature of Gushfil deposit is 223 to 302ºC. It is formed by NaCl and CaCl2-bearing fluid with 9.5 to 16.7 wt. % salinity. Host rock type, stratabound and epigenetic mineralization, post- sedimentary fault controlling, texture, ore types and gangue minerals, and no associated with igneous activity indicate Gushfil deposit is similar to MVT deposits, but ore-fluid temperature is higher than typical mineralization in the world.

The Dardvey iron deposit, central part of the Sangan mining area, is located in 300 Km southeast of Mashhad and structural zone of eastern Iran. The Dardvey ore deposit is a typical magnetite-rich skarn developed along the contact of Sarnowsar granite with high magnesium carbonate. Skarn zones of Dardvey deposit comprises of exoskarn, endoskarn and ore zones. The exoskarn zone includes, sub-zones of pyroxene skarn, garnet skarn and epidote-phlogopite skarn. According to Electron Micro Prob Analysis (EPMA), the composition of clinopyroxene is diopside-hedenbergite (from Di46–Hd52 to Di96 Hd3), and composition of garnet is andradite-grossular (from Ad35–Gr63 to Ad60 Gr39). In the skarns zones, there is a compositional variation with increase in Mg and decrease in Fe from the endoskarn to the retrograde skarn. Due to the change of oxidation state towards reduced conditions during paragentic sequences, sulfide saturation was occur. Sulfide saturation produces pyrrhotite, chalcopyrite, and pyrite that simoltaneously and post-dates magnetite and early calc-silicate formation, are other evidences of reducing conditions. Based on content of V, Cr, Ni, Ti, Ca, Al and Mn on magnetite, Darvay magnetite is located in skarn ore deposit. Also, due to existence of endoskarn zone, scapolite and Mg-rich minerals, Darvay skarn is classified as magnesian -calcic skarn.

Gazestan deposit is located about 185 km of Yazd, in the Bafgh – Posht e Badam Metallogenic belt, consists of Infracambrian carbonate, shale, tuff, sandstone and volcanic rocks. Acid to basic green rocks (rhyolite, dacite and basalt) are host for iron and phosphate mineralization. The alteration process is more intence in the volcanic rocks including, actinolite, chloritization, silicification and argilic. Also the host rocks altered strongly. Mineralization contains iron oxides and apatite associated with a minor amount of quartz, pyrite and calcite. The form of magnetite - apatite in the altered host rocks, magnetite - pyrite apatite, silica bearing magnetite, hematite and hematite magnetite ores. Also high LREE / HREE ratio and Eu negative anomaly could be indicative of a magmatic source. Therefore, origin of the Gazestan iron ore deposit is similar to Sweden Kiruna type.

One of the most prominent cases of the study of alteration processes and their effect on geochemistry is the ophiolite investigation. The Marivan-Palangan ophiolite (MPO) complex is a part of the Neotethyan ophiolites, which situated in the Kurdistan Province, western Iran. The studied samples reveal the occurrence of the secondary minerals such as epidote group, chlorite, zeolites, and less calcite and iron hydroxides in the form of veins, vesicles and fractures infilling, and replacement phases. The element concentration variation versus Loss on ignition (LOI), normalization of the samples as to fresh sample in the study area and standard sample, and immobile element modeling indicate that element contents changes vary depending on the degree of alteration so that the concentration of Large-Ion Lithophile Elements (LILE) such as Rb, Cs, K, Ba, and Na shown a significant increase. CaO and FeO oxides are relatively depleted. Light Rare Earth Elements (LREE) display slight enrichment, while Middle Rare Earth Elements (MREE) and Heavy Rare Earth Elements (HREE) are almost constant. Therefore, in evaluation of the geochemical characteristics of extrusive section of the MPO complex, the effect of alteration on the changes in the concentration of elements, in particular LILEs, CaO, FeO and also LREEs should be considered.

Late Neoproterozoic metamorphic – igneous rocks of the Shotor Kuh complex is located in the northern edge of the Central Iran structural zone. This complex crosscut by several Middle Jurassic diabasic dikes. Plagioclase, pyroxene and biotite are the essential rock-forming minerals of these dikes. Plagioclases have mostly andesine composition (An31-49). Pyroxenes have following compositions: En30-45Fs29-42Wo25-29. Biotites with XFe = 0.49-0.53 and XMg= 0.46 - 0.5 are mostly Mg rich biotites. Temperatures and pressures obtained from clinopyroxene thermobarometry are in the range of 1200-1100°C and 10-2 kbar respectively. By attention to the results of chemichal composition of these minerals, magma forming of these dikes has calc-alkaline nature and during their crystallization oxygen fugacity has been low. The mentioned dikes generated in a tectonic setting accommodate to intracontinental extensional regime such as a back arc basin (subduction of Neo-Tethys oceanic lithosphere beneath the Central Iran zone).

Ghazan-Khanik complex is a small mafic-ultramafic intrusive body with Permian age at the extremity of NW of the Sanandaj-Sirjan zone, has intruded into the Precambrian metamorphic rocks. Field studies, geochemistry mineral compositions and assemblages of them demonstrate this complex has four lithological zones. The lower zone of non-layered gabbro is the fine-grain gabbronoritic component and non-mineralized. The second zone include of non-apatite ultramafic, clinopyroxenite, verlite and minor amounts of dunite with high proportion of Fe-Ti oxide (25-30%). The pure Fe-Ti oxide mineralization (with highly 90%) occurred as sill-like cumulates parts within this ultramafic zone. The third zone consists of layered gabbro, which is occurred Fe-Ti oxide mineralization (0.5-5%) only in the apatite-rich mafic parts. The upper zone includes the anorthosite and pegmatite gabbro with 0-2% Fe-Ti oxide. Based on this studies for establishment of rich Fe-Ti oxide layers, two processes are involved; (1) enrichment in residual melts which is derived from basaltic parental magma and (2) injection of Fe-Ti oxide immiscible melts into mafic-ultramafic crystallizing mass.

Halalan Manganese ore deposit is located in Torud-Chah Shirin volcano-sedimentary band and the northern part of Central Iran structural-sedimentary zone. The outcropped rocks in the area include metamorphic complex with lithology composition of slate, phyllite, schist, marble, limestone, dolomite and slightly metamorphed sandstone with Early Jurassic age. Manganese mineralization has occurred in the form of stratiform (Layered and lens-shaped) and parallel to stratification. The main minerals forming the ore deposit are mainly pyrolusite, psilomelane, heulandite, braunite and hematite. The massive, layered, lentiform and bandy structures and the disseminated, the empty space filling and replacement textures are the most important structure and texture of the ore deposit. The existent alterations in the region include chloritic, epidote, argillic, silication and carbonatization alterations. Based on the geochemical studies, The high ratios of Mn / Fe and low concentrations of trace metals, especially Co, Ni, Cu, and high amounts of Mn, SiO2 and Fe are as evidences of Mn enrichment and depletion from submarine hydrothermal fluids (exhalative) in this deposit. Therefore, all the evidences indicate that the Halalan manganese ore deposit has formed under two mechanisms: the enrichment in seawater by exhalative-hydrothermal fluids and this deposition in sedimentary conditions influenced by changes in Eh and pH in marine environment and it is a volcano-sedimentary ore deposit. Based on the studies, the Halalan manganese ore deposit is most similar to the manganese ore deposits of Cuba type, with the exception that the Halalan manganese ore deposit has been affected by a metamorphic phase in the green schist facies.

One of the silver resources is Cu-Mo porphyry deposits, producing silver as by product. For this research, the results of analysis of 607 lithogeochemical samples for W, Zn, Ag, As, Ba, Co, Cu, Mo, Pb, Sb, Sn, Sr, Bi elements were used to investigate geochemical behavior of silver element in Hararan area which is located in the southeast of Iran and consists of copper mineralization seems to be connected to a porphyry Cu-Mo system. In this study, gap statistics and multivariate analysis techniques for identification anomalous areas of silver element and its associated elements were used. Anomalous areas maps achieved using gap statistics method showed that anomalous areas of Ag, Cu, Pb and zinc elements covered approximately each other. Dendrogram, which was earn from hierarchical cluster analysis, depict that Ag and Cu elements have associated with each other and formed one cluster. Although these elements are linked to Pb and Zn elements with lower correlation. As well, the results of factor analysis showed that the third factor include Cu and Ag elements with the highest eigenvalues. Consequently, geochemical bimodal behavior of Ag element i.e. accompaniment with Cu element by locating in Cu –bearing minerals such as chalcopyrite and bornite from one side and accompaniment with Pb and Zn elements by locating in mineral from other side was validated by using gap statistics and multivariate analysis techniques.

Lale zar granite batolith is located in the southeast of Urumieh-Dokhtar magmatic belt and Dehech-Sarduieh. This mass includes a low density of tourmaline with nodule, vein and solar morphologies. Less tourmaline occurs in this mass could be due to mass being saturated in the boron. The studied tourmalines are classified in the shourl-dravite series and alkaline group. Most of the substitutions in these tourmalines are kinds: Ca + Mg (O) = Na + Mg (OH), Ca = X–vac + Na، Ca + Mg = (X-vac + Al) – 1 and Mg instead of Fe. Existence of clear zoonings in the tourmalines, large amounts of Mg and less than 0. 6 amounts of FeO / FeO + MgO, show the growth of tourmaline in the open systems where generated from magmatic-hydrothermal and hydrothermal. On the other hand, high amounts of REE elements and enrichment of LREE than HREE, enrichment of the transition elements such as Cr, V, Ni, Cu, Zn, Zr also can be show the hydrothermal origin for these tourmalines.

The Piranshahr ophiolitic complex is located in NW Iran, and at north west of the Piranshahr town. Tectonically, the NW Piranshahr ophiolitic complex is severely mélanged and the boundary of different units in this complex is undistinguishable. Piranshahr ophiolite includes ultramafic, mafic, sedimentary and metamorphic rocks. Mafic rocks with basalt and diabase compositions are exposed in several parts of the region. In this paper, clinopyroxene geochemistry of basaltic rocks are studied and compared with the similar rocks from other supra-subduction zone-type of Eastern Mediterranean ophiolites. Clinopyroxenes display diopsitic compositions within the range of (En0.39-0.59 Fs0.01-0.05 WO0.50-0.57), calc-alkaline nature with low Ti and high Mg content. High-Mg and low-Ti magma suggest a supra-subduction zone setting for the formation of the Piranshahr ophiolitic basalts. According to the distribution of aluminum in clinopyroxenes, these minerals have formed at high oxygen fugacity and water content about 10 percent. The clinopyroxenes of the Piranshahr Ophiolite have similar chemical compositions to those of the other supra-subduction zone-type Eastern Mediterranean ophiolites (e.g., Troodos, Varinous, Pindos and Oman ophiolites) that show arc affinity.

Two new polymeric compounds of cadmium acetate using two isomers of pyridine hydrazide ligands have been synthesized and characterized by X-ray diffraction analysis. Structural analysis shows that both compounds were crystallized in monoclinic crystal system with P21/c space group. Coordination polymer [Cd(OAc)2(L1H)]n (1) which L1H is para pyridine hydrazide, has two dimensional sheets with rectangular net and coordination polymer [Cd2(OAc)3(L2H)L2(EtOH)]n (2) which L2H is meta pyridine hydrazide, has got herringbone structure in 2D dimension.

In this research, the effect of temperature and concentration of bismuth nitrate mole on structural, magnetic and photocatalytic properties of the bismuth ferrite nanoparticles prepared by nitrate-citrate method have been investigated. The structural and magnetic properties were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and vibrating-sample magnetometer at room temperature. An important role in the synthesis of pure bismuth ferrite is played by temperature and excess bismuth oxide. Analysis of XRD patterns and FTIR data indicate that to obtain the pure bismuth ferrite, a stoichiometric amount of bismuth nitrate mole in solution and sintering at temperature 650 °C is needed. The magnetic and photocatalytic results have showed that the presence of the impurity phases led to strong ferromagnetic behavior in samples, but has a negative effect on the photocatalytic properties of bismuth ferrite.

In this study, antimony substituted yttrium iron garnet with a composition of (x = 0, 0.1, 0.2) nanoparticles were fabricated by Sol-Gel method. Garnet phase formation were investigated by X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (Far FT-IR). X-ray diffraction results show that the samples in addition to garnet phase has impurity phases of YIP, α-Fe2O3 and Sb2O4 which are appeared with incease of Sb ion substitution. The garnet phase and impurity phases was calculated using the formula klug. Percentage of the Sb ion in dodecahedral sites were calculated. Finally, Magnetic properties of nanoparticles were investigated using a vibrating sample magnetometer (VSM).The VSM pattern show that the saturation magnetization of Sb-YIG decreases as increasing the Sb concentration.

Electrospinning is one of the most feasible techniques for producing nanoceramic fibers. In this paper, YBa2Cu3O7-δ (YBCO) superconductor nanofibers synthesized using electrospinning. The first step was preparation of a composite that is formed by mixing yttrium, barium, and copper acetates with different percent of polyvinyl alcohol (PVA). Then, the composite polymer has been electrospun to produce nanofibers. In order to obtain the calcination temperature, thermograviation analysis has been employed. Finally, for characterization, the nanofibers samples have been studied by, SEM, XRD, and ac magnetic susceptibility before and after sintering. The results showed that the best fibers in terms of diameter size and the absence of bead defects are attributed to 7.5 wt% of acetates. Also, the best sintering temperature for synthesizing the fiber sample of YBa2Cu3O7-δ was found 930 °C and the transition temperature of the fiber sample was obtained 93.2 K.