In the geological domain of the Patos Shear Zone there are several occurrences of asbestiform minerals, hosted in rocks with metaultramographic composition. In the region of Várzea Alegre, Granjeiro and Mangabeira the asbestos found in the lithotypes of the Granjeiro Complex were rudimentary exploited by prospectors who aimed at the performance of the physicochemical properties of this crystalline habit in commercial activities, especially the manufacture of asbestos tiles. The growing global trend of banning asbestos marketing has led to the devaluation of the material and the consequent abandonment of these mines. In the petrographic study, the fibrous or asbestos habit provides important information of the geological processes that acted in this region, characterized by the high temperature metamorphism that reached the partial melt of the rocks. Fibrous habit are regulated in the thermodynamic process of metamorphism in conjunction with the mobility of hydrothermal fluids interacting with antophyllite, tremolite and fibrolite. The petrographic, scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX) and X-ray diffraction (XRD) analyzes of the mineralogical associations present in outcrop lithotypes, including calcium-silicate and metapellitic rocks, define the conditions and processes caused in the stabilization of the minerals inherent in the shear zone and the deployment of the transpressive Duplex of Lavras da Mangabeira arrangement. The lithotypes were metamorphosed into high amphibolite and granulite facies, in the apical temperature range around 650-750 ° C. The petrogenetic associations indicate that the rocks were accommodated at different crustal levels and, therefore, exhibit mineral associations of low (± 250-350 MPa), medium (± 400-600 MPa) and high pressures (± 700-800 MPa). The percolation of secondary fluids, suctioned to low pressure zones through decompression exerted during the rock exhumation, is favored from the fault and horseback planes and performs the retrograde transformations of metamorphism. In retrometamorphism there is a destabilization of medium and high pressure minerals, the formation of porphyroblasts of mineral aggregates by matrix suction, and fracturing patterns filled with hydrominerals. In the interaction with secondary fluids, neoblastesis, replacement textures and pseudomorphism processes are generated, classified in the talcification, muscovitization or epidotization of the associations.
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