Citation: Grice, J. D.; Ercit, T. S.; Hawthorne, F. C. (1993). Povondraite, a redefinition of the tourmaline ferridravite Note: Atomic parameters updated by Grice on 11/20/2001. American Mineralogist, 78, pp. 433-436.
Formula: Al0.3 B3 Fe6.87 H3.12 K0.2 Mg1.83 Na0.8 O31 Si6
List type: noninterleaving
List: 3D
Basis: (1;0;0 0;1;0 0;0;1)
Dimensionality: 3
Formula: Al18 B9 Fe27 H9 Mg27 O96 Si18 (Al6 B3 Fe9 H3 Mg9 O32 Si6)
Multiplicity: 1