Iron Bromide: Bromine Vapour over Wet Iron Turnings

Iron bromide, Fe3Br8, is the step between bromine and potassium bromide. Thorpe (1912): bromine vapour, free of chlorine, is passed over wet iron turnings in a cast-iron or stoneware vessel; the solution is filtered, evaporated in cast-iron pans with enough extra bromine to reach Fe3Br8, and cooled to a black crystalline mass. Bromine vapour is poisonous: full protection, outdoors, never alone. The picture: our own drawing.