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• Acoustic and electrical measurements were performed on ilmenite-rutile aggregates. • Experiments were conducted at the pressure and temperature conditions of the lunar mantle. • Fe-Ti oxides increase the electrical conductivity and the seismic velocities of the lunar mantle. • Field datasets are reproduced with overturned ilmenite-bearing cumulates containing 20% melt. The overturn of titanium-rich mantle cumulates has been invoked to explain the structure and dynamics of the Moon. These dense cumulates are stable at the core-mantle boundary (CMB) and could explain field observations inferred from geophysical studies. We report acoustic and electrical experiments on natural ilmenite-rutile aggregates up to 4.5 GPa and 1920 K. Seismic velocities show a weak pressure and temperature dependence, with Vs ∼4.2 (+/-0.2) km/s and Vp ∼ 8.0 (+/-0.2) km/s at the CMB conditions. Conductivity increases by a factor of 104 from 373 to 1920 K and is >103 S/m above 1573 K. Seismic and electrical models for the lunar mantle based on our results, considering mixtures of Fe-Ti oxides and olivine, indicate that field velocity and conductivity estimates are reproduced satisfactorily with 3–16 vol.% Fe-Ti oxides and 20 vol.% melt. Interactions between a Ti-rich, melt-bearing layer and the adjacent core likely affect the cooling and magnetic history of the Moon. [ABSTRACT FROM AUTHOR]