Citation: Fischer, K. F. (1966). A further refinement of the crystal structure of cummingtonite (Mg,Fe)7(Si4O11)2(OH)2. American Mineralogist, 51, pp. 814-818.
Formula: Fe2.32 Mg4.68 O24 Si8
List type: noninterleaving
List: 3D
Basis: (1;0;0 0;1;0 0;0;1)
Dimensionality: 3
Formula: Fe14 Mg14 O48 Si16 (Fe7 Mg7 O24 Si8)
Multiplicity: 1