Citation: Brigatti, M. F.; Frigieri, P.; Ghezzo c; Poppi, L. (2000). Crystal chemistry of Al-rich biotites coexisting with muscovites in peraluminous granites Sample: A4. American Mineralogist, 85, pp. 436-448.
Formula: Al1.62 F0.04 Fe1.5 H1.8 K0.96 Mg0.76 Na0.04 O11.96 Si2.72 Ti0.22
List type: noninterleaving
List: 2D
Basis: (1;0;0 0;1;0)
Dimensionality: 2
Formula: Al12 F4 Fe6 Mg6 O28 Si8 Ti4 (Al6 F2 Fe3 Mg3 O14 Si4 Ti2)
Multiplicity: 1