Beusite

Fe_1.5Mn_1.5O₈P₂

Steele, I. M.Olsen, E.Pluth, J. J.Davis, A. M.

American Mineralogist (1991) 76, 1985-1989

a=8.757Å   b=11.381Å   c=6.136Å

α=90°   β=99.09°   γ=90°