The magnetite ore is generally sedimentary metamorphic type of magnetic iron ore which are mainly fine-disseminated; Gangue mineral is mainly composed of silicate minerals like quartz and hornblende etc. and some contains much iron silicate.
Since the magnetic iron ore is a kind of strong magnetic minerals, the iron ore concentrate of high grade and high recovery rate is obtainable by weak magnetic separation. Many medium- and large-sized magnetic separation plants usually adopt one-stage-grinding-magnetic separation process for ore grinding size bigger than 0.2-0.3mm; and two-stage-grinding-magnetic separation process for ore grinding size less than 0.2-0.3mm. If tailings can be separated by coarse grinding, stage grinding magnetic separation process shall be adopted. If some wall rocks or ores are mixed into the crushed product at each level during ore mining and a certain amount of gangue mineral appears, pre-separation through dry magnetic separator shall be conducted before ore grinding.