AM_Melilite_4 Formula: (Ge2.23 Si.77) Ca5 O11 Name: Melilite Unit cell: 10.912 8.695 11.0 90.0 96.87 90.0 , V=1036.18 Space group: C12/M1 (12)

Armbruster T , Rothlisberger F , American Mineralogist , 75 (1990) p.963-969, Crystal growth and structures of mixed-anion silicates-germanates:, Ca5[(Ge,Si)2O7][(Ge,Si)O4] and Na2Ca6[Si2O7][SiO4]2, sample Ca5Ge2.23Si.77O11