Abstract: There are 35.20% iron and 30.64% calcium oxide in specularite ore from Xinjiang.Iron mineral is mainly specularite，while gangue minerals are mainly calcite and quartz.The specularite is micro-fine disseminated in ore，and is a typical refractory iron ore.In order to study phase transformation of iron minerals during magnetic roasting process，effects of roasting temperature，roasting time and coal ratio on magnetic roasting results and phase transformation of iron minerals of specularite ore were investigated.The results indicated that iron concentrate with iron grade of 65.95%，recovery rate of 77.70% can be obtained under the conditions of coal powder with mass ratio of 12%，reduction temperature of 800 ℃ for 75 min，magnetic separation was brought at magnetic field intensity of 120kA /m after ground the roasted products at 90% passing 0.074 mm.Meanwhile，roasting temperature intense influences magnetic roasting process.When roasting temperature blew 800 ℃ Fe₂O₃，specularite can transform to Fe₃O₄ through magnetic roasting.The content of Fe₃O₄ is highest at roasting temperature of 800 ℃；when the roasting temperature is higher than 800 ℃，portion of Fe₃O₄ translated to FeO，and specularite is over-reduction.The content of FeO is highest under roasting temperature of 900 ℃；When roasting temperature rise to 1 000 ℃，portion of FeO will translated to metallic Fe.The process of phase transformation corresponds to results of magnetic separation.2CaO·Fe₂O₃ is produced at 900 ℃ resulted from portion of Fe₂O₃ reaction with CaO，which could not recovered by magnetic separation.The results can provide technical reserence for comprehensive utilization of specularite ore.

Key words: Specularite ore, Magnetic roasting, Roasting temperature, Phase transformation