Citation: Gibbs, G.V. (1966). The polymorphism of cordierite(I): The crystal structure of low cordierite. American Mineralogist, 51, pp. 1068-1087.
Formula: Al4 H1.5 Mg2 O18.75 Si5
Chemical name: Mg2 Al4 Si5 O18 (H2 O)0.75
List type: noninterleaving
List: 3D
Basis: (1;0;0 0;1;0 0;0;1)
Dimensionality: 3
Formula: Al20 Mg8 O72 Si28 (Al5 Mg2 O18 Si7)
Multiplicity: 1