مجله بلور شناسی و کانی شناسی ایران
سال بیست و یکم شماره 1 (پیاپی 51، بهار 1392)

Fyrouzeh mine is located about 55 km northwest of Nyshabour in the Provice of Khorasan Razavi. The exposed rocks are mainly volcanic and intrusive with intermediate composition and all of them are altered. This mine is the first type of IOCG reconized in Iran with Cu-Au-LREE-U. Besides Cu-Au-U, this area shows As, Mo, Zn and Th anomalies. Geochemical evaluation of stream sediment with regard to environmental concern revealed high Cu anomalies.  Rocks show high uranium anomalies (up to 35 ppm) higher than the standard values (1 ppm). Airborne radiometric maps show high U and Th anomalies in a broad area. Ag, Hg and Mn show anomalies within the stream sediments. Cu, Pb, Zn, Ag, Ni, Mn, Sb, Hg, and U content of both drinking and agricultural water are fourtunatly within the range of standard, only two samples have higher As content (more than 10 ppb).  High level of U-Th radiation and contamination of stream sediment with respect to Cu, Hg, Ag, Mn and agricultural water to As are important environmental issues and people health therefore they need to be study.

Lahijan granitoid pile, east of Gillan Province, petrographically comprises of mostly two group rocks: felsics (granite, porphyry granite and granodiorite) and mafics (diorite) and in terms of magmatic series belong to subalkaline and are mostly calcalkaline. The contact between the pile and surrounding rocks is faulty and includes myllonitic and cataclastic rocks yet there is no metamorphic haloe around it, so it has not intruded them and therefore unlike the previous statements it may not be Triassic in age. The presence of some similarities among trace element behaviors, especially REEs between felsic and mafic groups like, resemblance and enrichment of REE patterns, LREEs steep slope, flat patterns of HREEs, relative enrichment of LFSEs all suggest a common origin for them. The existence of ambiguous characteristics for example Aluminum saturation index (ASI) or molar Al2O3/(CaO + Na2O + K2O), P behavior, lack of observation sedimentary or basic microgranular xenoliths, abundance of biotite in felsic, hornblende and ouralitised pyroxene in mafic rocks, presence of individual apatite in felsic and lacking of it and low content of P2O5 in mafic rocks, Na2O/K2O wt% ratios, and amount of normative corundum, all propose that Lahijan granitoid is rather hybrid one instead pure I or S types. According to spider and discremenation diagrams, these intrusives belong to an arc setting.

East misho granitoid intrusion body, a part of Alborz-Azarbaijan zone, is located about 60 Km north west of Tabriz, NW Iran. This pluton with an area of about 50 km2 has cut percamberian unmetamorpic sedimentary rocks and, is covered with Permian sedimentary rocks with igneous nonconformity. Litological composition of the studied pluton displays a range of alkali granite, monzogranite and syenogranite. The dominant texture of the samples are granular, inequidimentional granular, pertite and myrmekite. Major minerals include quartz, K-feldspar and plagioclase, and minor and accessory minerals are biotite, amphibole, pyroxene, apatite, titanite and zircon. The Pluton composition is alkali-granite and displays metaluminous to peraluminous nature. Negetive Ba, Nb, Ti, Sr and Eu anomalies and enrichment in LILEs especially in Rb and Th suggests the crustal origin of these rocks. East Misho granitoid complex is continental margin and A- type post collision granitoides that, regarding negetive Nb anomalies belong to A2.

Nodoushan clay deposit is located about 130km southwest of Yazd city in the Uromieh-Dokhtar volcano-plutonic belt. Based on the field, mineralogical and geochemical studies, the rocks of Nodoushan area are of volcanic type and are composed of dacite, andesite and olivine-basalt, the pyroclastic type (crystalline tuff), and the microgranodioritic intrusive rocks. According to Zr/TiO2 versus SiO2 and Nb/Y versus Zr/TiO2 diagrams and field evidences, the mother rock of the deposit has dacite origin. The clay samples clearly indicate depletion of CaO, MgO, MnO and Na2O with respect to the original rock. The lack of high-temperature minerals such as pyrophyllite, dickite and, the presence of quartz, K-feldspar, kaolinite, halloysite and illite minerals in Nodoushan deposit indicate the alteration zone to be of intermediate argillic type. In this deposit, the average of Cr and Nb is 11.26ppm, which is less than the amount given for supergene deposits. High concentration of Sr + Ba (1341.33ppm) is due to the effect of hydrothermally processes. By referring to mineralogy, geochemistry as well as a model given by researchers, hydrothermal origin can be confirmed for Nodoushan clay deposit with some extent of weathering effect.

Pyralespite garnet group (Almandine group) is common minerals in the metamorphic and igneous complex of Boroujerd area. Moreover, Almandin (Fe enriched garnet) is the most common mineral but the content of Spessartin (Mn enriched garnet) is high in this area. The changes of mineral composition in different grains show that these minerals are zoning chemical and core to rim composition is varied. The garnet composition in core to rim respectively in granodiorite changes to Alm0.65, Prp0.05, Sps0.264, Grs0.193 in core to Alm0.76, Prp0.05, Sps0.14, Grs0.04 in rim, in pegmatite, Alm0.71, Prp0.02, Sps0.26, Grs0 in core to Alm0.76, Prp0.03, Sps0.2, Grs0.007 in rim of pegmatite, and in hornfels, Alm 0.81, Prp0.07, Sps 0.09, Grs0.03 in core to Alm 0.63, Prp0.06, Sps 0.3, Grs0.002 in rim. Petrography (for exampl, crystallization of tourmaline to garnet pegmatites and Andalusite to granodiorites) and mineral chemistry (oscillatory zoning Al in pegmatite garnet, Mg decrease and Mn increase in granodiorites garnet and liner trend Al in garnet hornfelse) show that metamorphic source for garnet in granodiorite and hornfels and magmatic source for pegmatites.

The Alborz structural zone in northern Iran is the host of a number of bauxite deposits. The Gheshlagh bauxite deposit is one of them with more than 2 km long and a thickness of about 20 m in the eastern part of the Alborz structural zone. This deposit has been developed as a stratiform horizon along the contact zone of Permian limestones and Triassic dolomitic limestones. The basal contact zone of the bauxite horizon is mainly undulatory, whereas the upper contact zone is concordant with the hanging-wall dolomitic limestones. Based on mineralogical and textural evidences, the horizon can be divided from top to bottom into five distinct units: (1) upper bauxite unit with a thickness of about 5 m, is composed of boehmite, hematite, kaolinite, rutile and svanbergite, 2) upper kaolinite unit approximately 2-3 m thick and is composed mainly of clay minerals, 3) hard bauxite unit with a thickness of approximately 1.5 m, mainly consists of hematite, kaolinite, boehmite and diaspore, 4) lower kaolinite unit approximately 1-4 m thick and is composed of kaolinite, boehmite and diaspore, and 5) lower bauxite unit about 4-6 m thick. Textural analyses indicate both allochthonous and autochtonous origins for these deposits. Combination of geological, textural and mineralogical data of the Gheshlagh bauxite deposit correspond to a boehmitic-diasporic karst bauxite deposit type.   

The study area is located about 20 km north-west of Hashjin, SW of Ardebil Province and is a part of Kejal-Shamsabad zone in the Tarom-Hashjin volcanic belt. Zeolite and associated minerals, such as quartz and calcite, are formed in cavities and fractures of trachy-andesitic country rock. Studies of zeolitic alteration zones show that stilbite is the main mineral and illite, sanidine, chlorite, calcite and, quartz are minor minerals. Based on petrographic studies, the main minerals of country rocks are plagioclase, k-feldspar, augite with volcanic glass and illustrate porphyritic texture. Geochemical studies and mass-changes calculations on the major and minor elements show that the elements such as Na, K, Ca, Mg, Fe and Mn depleted and Al and Si enriched in altered rocks relative to initial tracky-andesite. The rare-earth elements, except Eu and the HFS elements, have relatively similar behavior and show enrichment with increasing alteration whereas the LIL elements have different distribution patterns in altered and fresh rocks. Hydrothermal origin of zeolites are supported by evidences such as the euhedral crystals, open-space filling and amygdaloidal textures and the absence of main burial or contact metamorphic minerals. Stability field of zeolite is controlled by aqueous silica activity and temperature. Stilbite is stable in log (aSiO2) of -4.1 and forms at temperatures <100º C and pH of 8-9.

Intrusion of the Alvand plutonic complex into the pelitic and sim-pelitic rocks of the Tuyserkan area has caused the development of a thermal aureole in the Sarabi area. The rocks within the aureole are thermally metamorphosed and formed different types of hornfelses. High-grade metamorphic rocks with chemically suitable compositions were melted adjacent to the contact due to the heat from the pluton. Heat derived migmatization in high-grade metamorphic and adjacent to the contact is observable. Scale of partial melting and volume of produced melt are very small. Main minerals in the light colored parts of the migmatites (leucosomes) include quartz and K-feldspar with an igneous texture specially euhedral to subhedral texture of K-feldspar, in which interstitial – textured – quartz filled their interspaces, Textural differences between light leucosomes and dark melanosomes, mineralogical composition of the leucosomes, existence of igneous textures within the leucosomes and restriction of the leucosome formation to the pelitic rocks all are distinct evidence for occurrence of partial melting in the Sarabi area aureole. The liable reactions for melting include fluid-present reactions and fluid-absent reactions. High-grade metamorphic assemblages contain corderite, sillimanite and garnet. Mineralogical compositions of leucosomes resemble leucogranites resulting from partial melting. This indicates crystallization of the leucosomes from a silicate melt.

Tarikdarreh prospect area is situated in northeastern Iran at the boundary between Central Iran and Kopet-Dagh structural zones. Torbat-e-Jam granitoid intrusion of Triassic age is the main magmatic display in the district. These plutonic rocks with NW-SE trending intruded Miankouhi Formation (Upper Triassic) consisting of coaly shale, siltstone and sandstone converting those to hornfels for tens of meters around the plutons. Heavy mineral studies resulted in detecting minerals such as gold, scheelite, arsenopyrite, malachite, barite, jarosite, hematite, magnetite, specularite, galena, pyrite and garnet. Stream sediment analysis have shown anomalies of As, Cu, Bi, Co, W, Fe and Ti and a positive relationship between gold and As, Bi and Cu. Further exploration based on systematic sampling of soils around the plutonic rocks through determining statistical parameters for distribution of elements and fitting variogram of logarithmic data, has determined the anomaly threshold and quantified possible and probable anomalies. According to multi-variable statistics and factor analysis, the As, Cu, Au, Co, Fe, Mn and Ti, (W, Sb) package has a meaningful relationship with gold mineralization. The accomplished studies, as well as findings from heavy mineral, stream sediment and soil sampling show an interesting display of As, Au and to some extent Cu anomalies. Secondary dispersion halo maps for gold and its pathfinder elements such as As, Cu and Bi as well as factor analysis and additive index imply a high potential for gold in the Tarikdarreh prospect area.

The objective of this study was to investigate the clay mineralogy of soils derived from different parent materials in Binaloud zone, western Mashhad. Two soil profiles on the summit of granitic, ultrabasic and metamorphic rocks were described and sampled from genetic horizons. Clay fraction of the soils was analyzed using X-ray diffraction method. Chlorite, smectite, mica, amphibole and regularly interstratified chlorite/smectite and chlorite/mica are the most important clay minerals in the studied soils. Chlorite in ultrabasic soils and parent material of metamorphic soil is Mg-rich in contrast to Fe-rich chlorite in granitic soil. Amphibole was common in ultrabasic soil and metamorphic soil had much less amphibole. The eolian origin has been identified for mica in ultrabasic soil. As a result of higher weathering intensity in ultrabasic soil, the aboundance of regularly interstratified clay minerals were higher than the other soils.

The Alvand intrusive complex is located in south of Hamedan in Sanandaj-Sirjan Zone. This complex is composed of mafic to felsic rocks such as gabbro, diorite, tonalite, granodiorite, granite, aplite and pegmatite. Granitoid rocks comprise major part of the complex. Granitoids can be divided into two categories: porphyroid granitoids and hololeucocratic granitoids. Porphyroid granitoids are K-rich but hololeucocratic granitoids are K- poor. Petrographical and geochemical properties of granitoid rocks are seperate and they are not produced from a unique magma sources. Hololeucocratic granitoids in contrast to porphyroid granitoids are rich in CaO, Na2O and Al2O3 and poor in K2O, FeO and MgO. They are not producted from fractional crystallization of other granitoids. ΣREE and (La/Yb)N in hololeucocratic granitoids have wide range than other rocks. Eu/Eu* ratios in Porphyroid granitoids is 0.38-0.61 in hololeucocratic granitoids is 0.52-11.31 and in aplites is 0.15-2.15.  Porphyroid granitoids show negative Eu anomaly according to their crustal source. Considering that hololeucocratic granitoids are rich in Na2O and CaO, they are plagioclase rich and hence show positive Eu anomaly related to replacement of Ca by Eu in this mineral. Aplites and pegmatites of the region have characteristics resemble to porphyroid granitoids and are probably generated by differentiation of them.

Addition of EDTA to the KDP solution is an effective method to increase the stability zone and the crystal growth rate. EDTA neutralizes the chemical activity of metal ions impurity such as Al+3, Fe+3, Cr+3 (that exist in the chemical materials as impurity). Effect of Al+3, Fe+3, Cr+3 ions on the KDP crystal is investigated. Growth method was based on the “point seed” method following spontaneous growth at room temperature in a solution with optimum concentration. UV-Visible spectrum of the crystal containing Al3+ displays an undesirable increase of the optical absorption in the ultraviolet region. In fact, (AlO4)2- ions are present in the KDP crystals and give rise to ultraviolet absorption. Addition of EDTA to the KDP solution lead to decrease the optical absorption in the ultraviolet region and equal growth rate at all faces of the crystal.

(Bi2Te3)0.25(Sb2Te3)0.75 solid solution is a p type thermoelectric compound with optimum efficiency among the (Bi2Te3)x (Sb2Te3)1-x compounds with variable x. Increment of Bi2Te3 segment in the Bi-Sb-Te system decrease in hole concentration, which result in carriers transport tuning, an increment of Seebeck coefficient and decrement of electrical and thermal conductivities. An excess of Tellurium up to 4wt% further elevates the thermoelectric efficiency (η), thus resulting in an increase in the figure of merit. Structural characterizations of this compound in the absence and presence of added Te were carried out by means of X-Ray diffraction measurement, electron backscattering diffraction and atomic force microscopy. Detailed analyses carriers transport behavior reveal the intrinsic structures formation and minimum defects during crystallization resulted in the excess of Te. The analysis show a maximum figure of merit at 3wt% excess Te.

In this paper, nanoparticles of M- type strontium hexaferrite doped with cobalt SrFe12-xCoxO19 (x= 0-2) were synthesized via sol– gel technique. Structural and morphological properties of the samples were analyzed by X- ray diffraction (XRD), Fourier transform infrared spectroscopy (FT- IR) and scanning electron microscopy (SEM). The XRD results showed that all of the samples of SrFe12-xCoxO19 with x≤0.5 were single-phase. It seems that the Fe3+ ions are substituted by Co2+ ions in the crystallographic sites of the SrFe12O19 structure, but for the samples with x>0.5, the phase of CoFe2O4 is appeared in the samples and suggests that the Co2+ ions also make distinct phase in the samples. The value of the lattice constant a is almost kept unchanged but that of lattice constant c decreases with increasing dopant contents. The FT- IR frequency bands in the range of 560–580 cm-1 and 430– 470 cm-1correspond to the formation of tetrahedral and octahedral clusters of the metal oxides in ferrites, respectively.

Zinc (II) complex, [Zn(25-MBTSC)2I2] (1), where (25-MBTSC = (E)-2-(2,5-dimethoxybenzaldehyde) thiosemicarbazone, has been synthesized from the reaction of ZnI2 with 25-MBTSC in methanol as solvent at 25 ºC. It was characterized by elemental analysis (CHN) and is confirmed by single-crystal X-ray diffraction analysis. The complex 1 crystallizes in a triclinic system, with space group P-ī, having one symmetry-independent Zn2+ ion coordinated in a distorted tetrahedral geometry by two S atoms of the 25-MBTSC ligand and by two I atoms. The thiosemicarbazone ligand 25-MBTSC acts as a monodentate ligand and coordinates via one S atom in η1-S bonding mode to the zinc center.

New Schiff-base compound (E)-4-methoxy-N-(4-hydroxybenzylidene) aniline has been synthesized from the reaction of 4-hydroxybenzaldehyde with 4-methoxyaniline in methanol at 50ºC, and has been characterized by using elemental analysis and FT-IR spectroscopy. The crystal structure of the title compound has been determined by single crystal X-ray diffraction study. The title compound crystallizes in the orthorhombic, space group Pbcn with unit cell parameters a = 22.3813(5), b = 10.7477(2), c = 9.3623(2) Å, V = 2252.08(8) Å3, Z = 8 and R = 0.03. The N1 = C7 imine bond length of 1.2839(14) Å is typical of a double bond. The molecule of the title compound is non planar and the dihedral angle between the two phenyl rings is 58.97 (32)º. There is a strong intermolecular hydrogen bond of the O∙∙∙H-C type forming one-dimensional chain.