This sample of manganotantalite is displayed in the Smithsonian Museum of Natural History. Manganotantalite is a oxide mineral of manganese. niobium, tantalum and iron with the composition (Mn,Fe)(Ta,Nb)2O6. The sample at left is about 10 cm across and is from Rio Grande do Norte, Brazil.
Mindat treats manganotantalite as a synonym for columbite-Ta.