AM_Aenigmatite_2
Formula: Mg2.163 Si3.188 Fe.65 Na O10
Name: Aenigmatite
Unit cell: 10.328 10.724 8.805 105.15 96.85 125.47 , V=719.67
Space group: P-1 (2)

Gasparik T , Parise J B , Reeder R J , Young V G , Wilford W S , American Mineralogist , 84 (1999) p.257-266, Composition, stability, and structure of a new member of the aenigmatite group,, Na2Mg4+xFe2-2xSi6+xO20, synthesized at 13-14 GPa