A deflector (1) for attachment to a spiral separator (2), for capturing and redirecting a portion of a flowing stream of material (5). The deflector (1) includes an attachment means (3), to attach the deflector (1) to the spiral separator (2), a capturing portion (4) to capture a portion of the flowing stream (5), and, a redirecting portion (6) to emit a portion (7) of the stream. A method of separating particles of different densities using the deflector device (1) in conjunction with a spiral separator (2) is also disclosed.