Abstract: An ultra low grade magnetite from Dabagou, Inner Mongolia only contains iron grade of 15.68%, and 21.81% iron exists in form of ferric metasilicate.Meanwhile few fine magnetite grains are parceled in garnet and biotite, so it is hard to liberate.Beneficiation tests were carried out in order to provide basis for developing the ore.The results showed that iron tailing with production rate of 54.16% and iron grade of 7.71% was discarded by dry separation of lump ores, closed-circuit high pressure roller mill, and dry separation of fine ores, which increased iron grade from 15.72% to 25.19% with only 4.68% of magnetic iron lost.Iron concentrate with iron grade of 65.52%, total Fe recovery of 57.39% and Fe recovery of 78.14% was received by dealing with primary concentrate through the process of stage grinding, fine screen classification and stage low intensity magnetic separation.

Key words: Ultra low grade magnetite ore, Pre-magnetic separation, Stage-grinding and stage-separation