AM_Werdingite Formula: Fe.37 Al6.25 Mg.84 Si2 B2.54 O18.5 Name: Werdingite Unit cell: 7.995 8.152 11.406 110.45 110.85 84.66 , V=650.51 Space group: P-1 (2)

Niven M L , Waters D J , Moore J M , American Mineralogist , 76 (1991) p.246-256, The crystal structure of werdingite, (Mg,Fe)2Al12(Al,Fe)2Si4(B,Al)4O37, and, its relationship to sillimanite, mullite and grandidierite