AM_Na11K89MgF3
Formula: (Na.11 K.89) Mg F3
Name: Na.11K.89MgF3
Unit cell: 3.9824 3.9824 3.9824 90.0 90.0 90.0 , V=63.16
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 = .89