AM_Na44K56MgF3 Formula: (Na.44 K.56) Mg F3 Name: Na.44K.56MgF3 Unit cell: 3.9494 3.9492 3.9492 90.0 90.0 90.0 , V=61.60 Space group: PM3M (221)

Chakhmouradian A R , Ross K , Mitchell R H , Swainson I , Physics and Chemistry of Minerals , 28 (2001) p.277-284, The crystal chemistry of synthetic potassium-bearing neighborite, (Na1-xKx)MgF3, Sample x = .56