AM_Pargasite_53 Formula: Na.43 K.1 Fe1.55 Mg2.98 Al.86 Ti.21 Ca1.85 Mn.02 Si7.49 H1.958 O23.958 F.042 Name: Pargasite Unit cell: 9.869 18.058 5.32 90.0 105.03 90.0 , V=915.67 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(5)