The influence of microwave radiation on the magnetic properties of molybdenite and arsenopyrite has been investigated. Pure samples of the studied minerals were subjected to microwave radiation using different power levels and different time intervals. The effect of microwave treatment was monitored through magnetic susceptibility measurement, XRD, XPS and the proportion of mineral recovered relative to magnetic fraction on a dry magnetic separator. Microwave treatment caused significant changes in the magnetic characteristics of arsenopyrite samples. The magnetic susceptibility of this material increased from a negative value for the fresh sample to a strong, positive one after treatment at 500 W for 60 s. Additionally, the magnetic recovery was significantly increased to 98% compared to 0% for the fresh sample. In contrast with arsenopyrite, microwave-treated molybdenite showed no change in either its magnetic susceptibility or its magnetic recovery. The mineral remained nonmagnetic with 0% magnetic recovery. XPS and XRD results showed that arsenopyrite treatment with microwaves led to the formation of ferromagnetic phases, while molybdite (MoO3), a nonmagnetic material, was formed after molybdenite microwave treatment. The results of this work demonstrate the efficacy of magnetic separation following microwave treatment in the separation of arsenopyrite from molybdenite. (C) 2017 Elsevier B.V. All rights reserved.