Huntite mineral, which was taken from Denizli Acipayam mines in Turkey, was used as reinforcement for unsaturated polyester in this study. For this aim, firstly huntite mineral was characterized by X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR). Then huntite reinforced polyester composites were produced at various huntite concentrations (1, 3 and 5 wt.%) and characterized. Tensile and flexural strengths of polyester were obtained to increase until the huntite content of 3% into unsaturated polyester. Thermogravimetric analysis (TGA) was carried out to determine the thermal stability of the composites. When 3% huntite was added to the unsaturated polyester, maximum decomposition temperature of polyester increased from 383 degrees C to 398 degrees C. Differential scanning calorimetry (DSC) analyses of polyester and huntite reinforced polyester composites show a well-cured composite. The distribution of huntite particles in polyester matrix was observed by scanning electron microscopy (SEM). The presence of huntite into polyester was confirmed by X-ray diffraction and FIR analyses. (c) 2012 Elsevier Ltd. All rights reserved.