A linear motor properly wound can serve as a mechanism for separating paramagnetic sulphide minerals, like pyrrhotite, from other sulphides and associated gangue minerals. The effectiveness of separation depends on the energising current of the separator, the frequency of the ac cycle, and the particle size of the minerals. The speed of travel of the minerals over the surface of the separator is also a function of particle size, and appears to be constant._x000D_
The movement of pyrrhotite, magnetite and iron filings of comparable size fraction (150 m +74 m) on the linear motor surface has been observed using a cine camera._x000D_
An attempt, has been made to give a theoretical basis for the movement of the particles by calculating the minimum electrical energy required to move them._x000D_
Further, the rate of decay of magnetic moment of the particles has been estimated for magnetite and it has been found that sufficient residual magnetism existed in the particles after they had been exposed to the first half of an ac cycle for them to have like polarity with the second half of the cycle. The particles are therefore repelled from the motor surface every second half of the cycle. This repulsion due to remanent magnetism is the probable cause of particle movement over the linear motor surface.