Abstract Tourmaline is present as alteration and mineralization at Maherabad and Khopik Cu-Au prospecting areas, Najmabad Sn-W-Au prospecting areas, Hired Au-Sn prospecting area, and within Gheshlagh pegmatite dikes. Based on X-ray diffraction graphs, Maherabad, Gheshlagh and Hired tourmaline are schorl, but Najmabad and Khopik are dravite type. Based on chemical composition, all of tourmalines are belong to alkali group. The Mg/(Mg+Fe) ratio in Gheshlagh tourmaline is 0.21-0.29, in Hired is 0.32-0.47 and in Maherabad is 0.44-0.5 and in Najmabad and Khopik are Mg/(Mg+Fe)= 0.55-0.82. Khopik tourmaline contains considerably higher Mg (1.9-2.3) compared with the Maherabad (Mg= 1.4-1.9). The average TiO2 content of Maherabad tourmaline is 0.35 and Khopik is 0.19. At Khopik, deeper portion of the porphyry Cu-Au is exposed. Najmabad tourmaline contains the highest Mg (Mg= 2.2) and Gheshlagh the lowest Mg (Mg=0.5-0.7) and highest Fe (Fe= 1.9-2.3). Najmabad tourmaline contains the highest TiO2 (0.48%) and other tourmaline contains less than 0.3 % TiO2. In general, there is a reverse correlation between CaO and Na2O. Gheshlagh has the lowest CaO and highest Na2O. The CaO and Na2O content of tourmaline from Hired are very variable.

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