To easily separate game media from foreign substances.

A passage 2 for game media of pachinko game balls is connected to the discharge hole 5a of a polishing device 5. In the passage 2 there is disposed a belt conveyer 3 which constitutes part of the passage 2. Below the belt conveyer there is provided a recovering chamber 13 in which a removing body 4 is installed. Foreign substance M can stick to the surface of the belt 3a of the belt conveyer 3, which rotates in the direction opposite to the moving direction of the game medium P at the time of the removal of foreign substances. The removing body 4 can remove the foreign substance M sticking to the belt 3a and the foreign substance recovering chamber 13 recovers the foreign substance M separated from the belt conveyer 3 by the removing body 4.