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We performed experiments between two different carbonated eclogite-derived melts and lherzolite at 1375°C and 3 GPa by varying the reacting melt fraction from 8 to 50 wt %. The two starting melt compositions were (1) alkalic basalt with 11·7 wt % dissolved CO₂ (ABC), (2) basaltic andesite with 2·6 wt % dissolved CO₂ (BAC). The starting melts were mixed homogeneously with peridotite to simulate porous reactive infiltration of melt in the Earth’s mantle. All the experiments produced an assemblage of melt + orthopyroxene + clinopyroxene + garnet ± olivine; olivine was absent for a reacting melt fraction of 50 wt % for ABC and 40 wt % for BAC. Basanitic ABC evolved to melilitites (on a CO₂-free basis, SiO₂ ∼27–39 wt %, TiO₂ ∼2·8–6·3 wt %, Al₂O₃ ∼4·1–9·1 wt %, FeO* ∼11–16 wt %, MgO ∼17–21 wt %, CaO ∼13–21 wt %, Na₂O ∼4–7 wt %, CO₂ ∼10–25 wt %) upon melt–rock reaction and the degree of …