Bismutoferrite is a rare, ferric iron bismuth silicate, first recorded from Schneeberg District, Erzgebirge, Saxony, Germany, in 1871 and named for its composition. Bismutoferrite is yellow to green, finely crystalline, powdery, earthy, or massive; it rarely occurs as divergent sprays of prismatic crystals. It is interpreted to be of hydrothermal origin. Bismutoferrite is found at numerous localities in Baden-Wurttemberg, Bohemia, Bavaria, and Saxony states, Germany, and in Smrkovec, Slavkovsky, Les Mountains, Marianske Lazne, Bohemia, Czech Republic. It occurs in England,at several localities including: South Terras mine, St. Stephen-in-Brannel, Hingston Down quarry, Calstock, Cornwall, and at Buckbarrow Beck, Carney Fell, Cumbria. Bismutoferrite occurs as excellent crystals from the Dientje mine, Bourkes Luck, Pilgrims Rest, Ehlanzeni District, Mpumalanga Province, Transvaal, South Africa. Notable US localities include: the Lodi # 4 claim, Plumas Co., California, and in the Organ Mountains, Dona Ana Co., New Mexico.