Citation: Brigatti, M. F.; Frigieri, P.; Poppi, L. (1998). Crystal chemistry of Mg-, Fe-bearing muscovites-2M1 Sample GFS15Ab from peraluminous granites at Sardinia, Italy. American Mineralogist, 83, pp. 775-785.
Formula: Al2.83 Fe0.06 H0.32 K0.92 Mg0.08 Na0.08 O12 Si3.04 Ti0.02
List type: interleaving
List: 2D
Basis: (1;0;0 0;1;0)
Dimensionality: 2
Formula: Al14 Fe4 H4 Mg4 O28 Si8 Ti4 (Al7 Fe2 H2 Mg2 O14 Si4 Ti2)
Multiplicity: 1