Morphology, composition and dissolution of chromite in the Goro lateritic nickel deposit, New Caledonia: Insight into ophiolite and laterite genesis

•Chromite morphology indicate formation in a supersaturated parent melt under changing cooling conditions.•Chromite geochemistry indicate a highly depleted and reduced melt of boninite-type affinity.•Dissolution of chromite occurred by abiotic and biogenic means.•Dissolution textures and geochemistry support the role of Mn-oxidizing bacteria in leaching Cr from chromite.•Chromite dissolution supports an alternative goethite crystallisation mechanism for the oxide zone at Goro.