The Heavy Media Cyclone may be lined with very high quality ceramic tiles or manufactured from Ni-hard (a very hard alloy of cast iron containing nickel) with a specially designed helical profile. A cyclone is the heart of the washing unit in a Heavy Media Washery. It is a non moving part and hence requires very low maintenance. However, the pressure at the inlet of the cyclone is a very important factor and it is suggested to maintain a minimum pressure of around D x 9 x 9.81 x density/100 (in bars), where D = the inner diameter of the cyclone in mm. It is important to note that the pressure at which pulp (mixture of coal and magnetite) is introduced in the cyclone is the principal means of controlling the forces within the cyclone. With the decrease in pressure more coal shall report to the discard/middlings, thus impairing the efficiency of separation.