AM_Grandidierite
Formula: (Mg.976 Fe.024) Al3 B Si O9
Name: Grandidierite
Unit cell: 10.325 10.9575 5.76 90.0 90.0 90.0 , V=651.66
Space group: PBNM (62)

Dzikowski T J , Groat L A , Grew E S , American Mineralogist , 92 (2007) p.863-872, The geometric effects of VFe2+ for VMg substitution on the crystal structures, of the grandidierite-ominelite series, Sample: G17, Locality: Madagascar