AM_Trembathite Formula: (Mg1.56 Fe1.44) B7 O13 Cl Name: Trembathite Unit cell: 8.588 8.588 21.05 90.0 90.0 120.0 , V=1344.52 Space group: R3C (161)

Schindler M , Hawthorne F C , The Canadian Mineralogist , 36 (1998) p.1195-1201, The crystal structure of trembathite, (Mg1.55Fe1.43Mn0.02)B7O13Cl, a mineral of, the boracite group: An example of the insertion of a cluster into a three-dimensional net