The title compound, dicerium(III) oxidodisilicate, Ce2[Si2O7], was obtained as a by-product in its H-type structure after attempts to synthesize CeSb2O4Cl from fused silica ampoules. It crystallizes isotypically with H-La2[Si2O7]. The four crystallographically distinct CeIII cations form distorted square antiprisms, capped square antiprisms, and bicapped square antiprisms as coordination polyhedra consisting of oxygen atoms. Four crystallographically different silicon atoms recruit the centers of two different isolated [Si2O7]6– units.
