Each phase corresponds to a new structure type that reveals unique structural motifs and different degrees of disorder. Phase A is a mixed silicate-oxide where silica-coordinated motifs are embedded within interconnected columns of yttrium-centred polyhedra that are characteristic of the high-pressure and high-temperature modifications of Y2O3. These unusual rare earth environments are located in a scaffold whose optical and thermal properties indicate promise as a host for activator ions to create phosphors for solid-state lighting. As a direct superstructure of Cs3CaBi[P2O7]2 , phase B features more conventional structural units but illustrates how those units can be assembled in a distinctive partially ordered manner on that extended framework, exploiting flexible silicate disorder to create appropriate coordination environments for the disordered cations. The persisting disorder suggests the prospect of chemistry leading to more completely ordered structures from targeted exploration of substitutional chemistry. Furthermore, a structural relationship between the cation arrangement in phase B and the Zintl phase Zr5Si4 64 aristotype reveals an unexpected perspective for the design of other silicate materials. Such opportunities illustrate the enabling nature of the discovery of new structure types, as they allow subsequent targeted modification, and the importance of developing the appropriate workflows to access them. These workflows can exploit multiple source