AM_Muscovite_12 Formula: K.88 Na.11 Al2.84 Fe.06 Mg.02 Si3.08 O12 H2 Name: Muscovite Unit cell: 5.229 9.076 20.322 90.0 95.74 90.0 , V=959.61 Space group: C12/C1 (15)

Catti M , Ferraris G , Ivaldi G , European Journal of Mineralogy , 1 (1989) p.625-632, Thermal strain analysis in the crystal structure of muscovite at 700 C, T= 700 C