The link of calc-alkaline magmatism and formation of goethite in northwest of Mahalat (Abegarm)

Goethite, as yellow pigment, mine is located in northeast of Mahalat in the Abegarm region. The ore is within Quaternary travertine and investigation of its formation is the aim of this study. The ore intruded young travertine in the form of dyke with breccia texture, suggesting the formation of the ore from magmatic source instead of its formation in a sedimentary basin. In polish section, primary hematite, which is replaced by goethite, is still observed. In recent years, separation and formation of iron ore from calc-alkaline magma have been suggested. The presence of hot spring close to the mine, suggests the effects of hot water to convert hematite to goethite in oxide condition with pH 6.5. Chemical and mineralogical changes in different parts of the ore body have been effected by this process. It seems that goethite in Abegarm, unlike most of well known goethite, did not formed during weathering process and it forms from calc-alkaline magma as hematite and then transformed to goethite due to the effects of hot water. Previous studies confirm the presence of calc-alkaline magma in the region.