In this study, the concentration of coal-pyrite and lignite taken from Yozoat-Ayridam (Turkey) Coal Management was investigated by oil agglomeration. In the previous studies, the agglomeration of coal-pyrite was investigated using different bridging liquids (fuel oil, diesel oil and kerosene) and the combination of reagent (KEX, Acorga M5397) + kerosene. When using only bridging liquids, the agglomeration recovery of pyrite was very low. To increase the hydrophobicity of pyrite, KEX was used. However, the pyrite was not agglomerated with an acceptable recovery. But when using Acorga M5397, which is a chelating reagent, the agglomeration recovery of pyrite was increased. The pyrite was agglomerated with a recovery of 76.70 wt% by single-stage agglomeration. In the optimum conditions which were determined for coal-pyrite, the agglomeration recovery of lignite was investigated. It was found that the lignite could not be agglomerated with an acceptable recovery. To investigate the separation of coal-pyrite and lignite, the artificial mixture of coal-pyrite and lignite was prepared with the weight ratio of 1/4 of coal-pyrite and lignite. It was found that the pyrite could be agglomerated at a recovery of 96.54% with three-stage agglomeration process. The lignite concentrate was produced with a recovery of 73.96 wt% and the pyrite content of 0.86 wt%. These findings showed that the coal-pyrite and lignite could be separated by oil agglomeration using appropriate reagent and bridging liquid. (C) 2002 Elsevier Science Ltd. All rights reserved.