AM_Columbite-(Mn)_9 Formula: Mn.782 Fe.14 Ti.034 Ca.01 Nb1.778 Ta.178 O6 Name: Columbite-(Mn) Unit cell: 14.395 5.753 5.083 90.0 90.0 90.0 , V=420.95 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=1 from Kragero, Norway, Sample: Annealed at T = 800 C for t = 24 h, Note: Occupancies calculated assuming complete Fe/Mn disorder