The phase formation and kinetics of metal reduction upon the interaction of natural iron-manganese tantalum niobates with carbon is studied using X-ray diffraction analysis, electron probe microanalysis, and thermogravimetry. The reducibility of the minerals increases in the series wodginite-tantalite-columbite. Reduction occurs in stages with the formation of niobium tapiolite and disordered tantalite and wodginite as intermediate phases.