The polyoxocations [Bi6O8]2+ and [Pb8O6]4+ are encapsulated in [(UO2)(O2)(OH)]2424- to form Li22 [(Bi6O8){(UO2)O2 (OH)}24]·nH2O (I) and Li16.8 [(Pb8O6)0.7(Pb8)0.2 (Pb6)0.1{(UO2)O2 (OH)}24]·nH2O (II) despite being stable on opposite ends of the pH scale in aqueous media.