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Which is more thermodynamically stable, Fe₂O₃ or Fe₃O₄?

I looked up the  :delta: G _f° for them both, and for Fe₃O₄ it was -1015.4 kJ/mol, while for Fe₂O₃ it was -742.2 kJ/mol. Since the Gibbs free energy for Fe₃O₄ is more negative, I thought it would be Fe₃O₄ that is more thermodynamically stable.

However, the answer is that Fe₂O₃ is the more stable one. Can someone tell me why please?

[Olympiad_Tutor]

Consider delta G for:

Fe₂O₃ -> Fe₃O₄ + O₂

[vasilews]

Fe₃O₄ can also be written as FeO.Fe₂O₃. That should lead you to an explanation...