AM_Columbite-(Mn)_2
Formula: Mn.789 Nb1.775 Fe.141 Ta.178 Ti.028 Ca.009 O6
Name: Columbite-(Mn)
Unit cell: 14.325 5.744 5.113 90.0 90.0 90.0 , V=420.71
Space group: PBCN (60)

Tarantino S C , Zema M , American Mineralogist , 90 (2005) p.1291-1300, Mixing and ordering behavior in manganocolumbite-ferrocolumbite solid solution:, A single-crystal X-ray diffraction study, Sample: KRA n4 Qm=0.565 from Kragero, Norway, Note: Occupancies calculated assuming complete Fe/Mn disorder