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Economic concentrations of Fe–Ti oxides occur as massive, conformable lenses or layers in the lower part of the Panzhihua intrusion, Emeishan Large Igneous Province, SW China. Mineral chemistry, textures and QUILF equilibria indicate that oxides in rocks of the intrusion were subjected to extensive subsolidus re-equilibration and exsolution. The primary oxide, reconstructed from compositions of titanomagnetite in the ores and associated intergrowths, is an aluminous titanomagnetite (Usp₄₀) with 40 wt % FeO, 34 wt % Fe₂O₃, 16·5 wt % TiO₂, 5·3 wt % Al₂O₃, 3·5 wt % MgO and 0·5 wt % MnO. This composition is similar to the bulk composition of the oxide ore, as inferred from whole-rock data. This similarity strongly suggests that the ores formed from accumulation of titanomagnetite crystals, not from immiscible oxide melt as proposed in earlier studies. The occurrence of oxide ores in the lower parts of the …