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The Zamin Hossein district is located about 170 km southeast of Kerman city in the Dehaj-Sarduieh metallogenic belt, SE Iran. Interaction of hydrothermal fluids with volcanic rocks (mainly andesite) of the Lower Eocene age in this district accompanied with occurrence of an extensive alteration system. The hydrothermal alteration system of the district includes argillic, phyllic and propylitic alteration zones. On the basis of microscopic observations, chalcopyrite, magnetite, pyrite, hematite, goethite, malachite and azurite are the most important minerals in the mineralized veins and veinlets of the argillic alteration zone. Mineralogical studies indicate that the argillic alteration zone contains minerals such as quartz, kaolinite, montmorillonite, muscovite-illite, jarosite, hematite, goethite, albite, orthoclase and calcite. Calculations of the mass changes of trace elements, assuming Al as the monitor immobile element, show that the process of conversion of andesitic rocks into argillic alteration zone accompanied with enrichment of elements such as U, Ba, Nb, Ga, Tl, Sr, Sc, Ta, Th and Mo, and depletion of elements such as Th, Co, Cs, Rb, V, Pb, Ni, Cu and Zn. Other trace elements, such as Hf, Y, Zr, and REEs, have undergone both leaching and fixation processes during development of the argillic alteration zone. The distribution pattern of normalized REEs to chondrite implies difererntiation and enrichment of LREEs ratio to HREEs and occurrence of weak negative Eu anomaly during development of the argillic alteration zone. Combination of the obtained results from mineralogical studies, geochemistry of mass changes, and investigation of correlation coefficients between elements reveal that the behavior of trace elements during the development of argillic alteration zone in the Zamin Hossein district is a function of factors such as changes in temperature and chemistry of solutions involved in alteration, differences in alteration intensity, adsorption by clay minerals, scavenging by metallic oxides and hydroxides, and fixation in the neomorph mineral phases.

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The RoudMajan kaolin deposit is located about 35 km northwest of Torbat-e- Heydarieh city, Khorasan Razavi Province, in the Great Kavir Block subzone. Field evidence and laboratories results indicate that this deposit is genetically associated with the alteration of basaltic andesite rocks (Lower Eocene). According to the microscopic evidence and various analytical techniques (XRD, SEM-EDS, FE-SEM, DTA and TGA), kaolinite, illite, haloysite, quartz, alunite and muscovite are the major mineralogical phases and hematite, pyrite, rutile, galena, barite, calcite, biotite, apatite, titanomagnetite and titanium augiteare the minor minerlogical phases in this deposit. Calculations of mass balance of elements with the assumption of Al, as a monitor immobile element, reveal that the development of the kaolinization process of andesi-basaltic rocks in the RoudMajan  has been accompanied with the enrichment of Pb, leaching of elements such as Cs, Rb, Cu, Zn and Sr and leaching and fixation of elements such as Hf, Ba, Zr, V, Th, Ta, Nb, Ga, Cr, Co and Ni. Among the lanthanides, only Ce experienced mass decrease, while others exhibit both incremental and decremental behavior during kaolinization processes. The distribution pattern of normalized REE to chondrite indicates the differentiation and enrichment of LREE from HREE. The obtained results reveal that the behavior of trace elements during the formation of the RoudMajan kaolin deposit is a function of factors such as changes temperature and mineralizing fluid chemistry, differences in alteration intensity, adsorption, scavenging, mineralogical control, and abundance of complexing ions. Correlation coefficients between elements indicate the role of clay minerals, secondary phosphates, rutile, manganese oxides, muscovite and illite in the distribution and fixation of lanthanides. The occurrence of negative anomalies of Eu and Ce in kaolin samples indicates the alteration of plagioclase minerals of primary basaltic andesite rocks by high-temperature fluids and reduction of oxygen fugacity during the development of the RoudMajan kaolin deposit.