Citation: Ohta, T.; Takeda, H.; Takeuchi, Y. (1982). Mica polytypism: Similarities in the crystal structures of coexisting 1M and 2M(1) oxybiotite. American Mineralogist, 67, pp. 298-310.
Formula: Al1.322 Fe0.864 K Mg1.638 O12 Si2.84 Ti0.336
List type: noninterleaving
List: 2D
Basis: (1;0;0 0;1;0)
Dimensionality: 2
Formula: Al14 Fe14 Mg6 O24 Si8 Ti4 (Al7 Fe7 Mg3 O12 Si4 Ti2)
Multiplicity: 1