Role of ore mineralogy in selecting beneficiation route for magnesite-dolomite separation

Characterization and beneficiation of magnesite-dolomite sample were performed. The role of ore mineralogy in selecting the most adequate concentration method for magnesite-dolomite separation was found to be detrimental. The microscopic analysis showed that dolomite is stained with goethite and lepidocrocite (weakly magnetic minerals), while magnesite is stained with hematite and magnetite (highly magnetic mineral). A dry magnetic separation technique was used to separate dolomite from magnesite. The magnetic separation of the sample resulted in a magnesite concentrate product assaying 1.12% CaO with 46.02% recovery and CaO/SiO2 molar ratio = 1.62. This magnesite product is suitable for basic refractory. Besides, middling fraction was produced, containing 44.63% magnesite and 10.95% dolomite. This product is suitable for making low-loss forsterite dielectrics.