The Davis Magnetic Tube Tester consists of an extremely powerful electromagnet which can generate a magnetic field intensity of up to 4,000 gauss, a glass separation tube and a motor driven agitation mechanism.

The tube is positioned between the poles of the magnet at an angle of approximately 45 degrees (the angle is adjustable).

During the operation of a small electric motor drives the agitating mechanism that supports the water filled glass tube.

The tube moves forward and backward while it rotates simultaneously. Any magnetic particles present in the product sample inside the tube are collected in the zone of intense magnetism. A vigorous washing action by agitation is applied to these magnetic particles. Eventually all nonmagnetic particles are flushed from the tube.

A clean concentrate of magnetic particles is then available for determining percent.