In this study, the changes in surface area, morphology and leachability of antimony and arsenic from tetrahedrite, jamesonite and enargite mechanically activated by a high-energy planetary mill were investigated. It appears that the leaching of antimony from tetrahedrite and jamesonite and arsenic from enargite in alkaline solution of sodium sulphide is temperature-sensitive reaction. The temperature dependencies of all reactions were investigated in the interval 313-363 K. Resulting experimental activation energies were E-a = 111- 182 kJ mol(-1) for mechanically activated minerals. The values of E-a are characteristic for processes controlled by surface chemical reactions. (c) 2006 Elsevier B.V. All rights reserved.