The sorting tank with a certain number of magnetic conductive stainless steel fiber (or steel plate mesh) is placed in the pin loaded solenoid coil. When the coil is energized, the magnetic conductive stainless steel fiber is magnetized and its surface will produce a highly uneven magnetic field, that is, high gradient magnetization magnetic field. When paramagnetic materials pass through the steel fiber in the sorting tank, they are absorbed on the steel fiber surface by a magnetic force proportional to the product of the applied magnetic field and magnetic field gradient, while the non-magnetic materials directly pass through the magnetic field, and non-magnetic material valve and pipe and finally flow into the non-magnetic product tank. If the weak magnetic material trapped by the steel fiber reaches a certain level (determined by the process requirements), the ore feeding is stopped. The excitation power is disconnected, and the magnetics are flushed, and the magnetics pass through the magnetics valves and pipes and flow into the magnetic product tank, then repeat the above procedures.