AM_Biotite_25 Formula: Si2.68 Al1.96 Fe1.36 Mg.72 Ti.16 (Na.02 K.98) O12 H1.56 Name: Biotite Unit cell: 5.328 9.222 10.197 90.0 100.26 90.0 , V=493.02 Space group: C12/M1 (12)

Brigatti M F , Frigieri P , Ghezzo c , Poppi L , American Mineralogist , 85 (2000) p.436-448, Crystal chemistry of Al-rich biotites coexisting with muscovites in, peraluminous granites, Sample: CC1