Rocks of charnockitic affinity---including anorthosites---are recrystallized under granulite facies conditions. It is shown that the stability relationships of some silicates (hornblende, biotite, sphene, and titanic augite) require a liberation of Ti and usually Fe from the silicate lattices under granulite facies conditions. Because titanic iron ore appears to develop in rock complexes recrystallized in granulite facies, it is suggested that there are some crucial genetic relationships between the liberation of ore elements from the silicates and the segregation of ore bodies in, or near, basic noritic rocks and anorthosites.We have reason to believe that the liberated titanium and iron diffuse in the form of atoms, ions, or molecules through the recrystallizing rock complexes and that structural and chemical heterogeneities determine where the ore minerals will consolidate.

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