AM_Armangite Formula: C Mn26 As18 O57 Name: Armangite Unit cell: 13.491 13.491 8.855 90.0 90.0 120.0 , V=1395.75 Space group: P11-3 (1)

Moore P B , Araki T , American Mineralogist , 64 (1979) p.748-757, Armangite, Mn26[As6(OH)4O14][As6O18]2[CO3], a fluorite derivative structure