AM_Mullite_3
Formula: Al2.25 Si.75 O4.871
Name: Mullite
Unit cell: 7.54336 7.69176 2.88402 90.0 90.0 90.0 , V=167.34
Space group: PBAM (55)

Balzar D , Ledbetter H , American Mineralogist , 78 (1993) p.1192-1196, Crystal structure and compressibility of 3:2 mullite