The Daixian rutile deposit is located in western Hengshan and belongs geotectonically to the central zone of North China Craton. Recent exploration shows that the Daixian rutile deposit is one of the largest rutile deposits in oft-com:office:smarttags" />China with reserves up to 3.7 million tons of TiO2. The Hongtang rutile orefield is one of the three main orefields in the Daixian rutile deposit. The rutile-bearing rocks mainly include anthophyllite schist, vermiculitized antinolite schist, albite-clinochlore-bearing antinolite schist and vermiculitized actinolite-bearing quartzite. The authors thus infer that the protolith of the rutile deposit is chemically equivalent to mid-ocean ridge tholeiite, and that the ore-bearing rocks were formed through crystallization differentiation of anorthite and other types of metamorphism and deformation. oft-com:office:office" />