AM_Norbergite_2 Formula: (Mg2.979 Fe.021) (Si.985 B.015) H.478 O4.486 F1.514 Name: Norbergite Unit cell: 4.711 10.275 8.805 90.0 90.0 90.0 , V=426.21 Space group: PBNM (62)

Camara F , The Canadian Mineralogist , 35 (1997) p.1523-1530, New data on the structure of norbergite: location of hydrogen, by X-ray diffraction, Sample: HV47 N1