AM_Pargasite_55 Formula: Na.47 K.1 Mg3.06 Fe1.45 Al.99 Ti.33 Ca1.83 Mn.02 Si7.31 H1.958 O23.958 F.042 Name: Pargasite Unit cell: 9.87 18.046 5.318 90.0 105.04 90.0 , V=914.76 Space group: C12/M1 (12)

Oberti R , Ungaretti L , Cannillo E , Hawthorne F C , Memmi I , European Journal of Mineralogy , 7 (1995) p.1049-1063, Temperature-dependent Al order-disorder in the, tetrahedral double chain of C2/m amphiboles, Sample: S(7)