PURPOSE: To permit the mirror surface polishing by supplying a workpiece, proper polishing members, and polishing oil into a barrel, revolving the rotary bottom part of the barrel by a barrel driving means, applying a centrifugal force on the content articles such as workpiece and polishing members, and allowing the content articles to flow and to be stirred between the rotary bottom part of the barrel, fixed frame part, and the inner peripheral surface of a porous plate.

CONSTITUTION: A workpiece, polishing members, and polishing oil are supplied into a barrel 1. In the mirror surface polishing, the organic group polishing member such as walnut chips and corn chips is desirably used as polishing member. The drive of a motor 11 is transmitted to a rotary bottom part 7 through a pulley 12, belt 10, pulley 9, and a rotary shaft 8. A centrifugal force is applied to the content articles by the rotary bottom part 7. Then, the content articles are tilted, and aslantly rise along the peripheral surface of a fixed frame part 2, guided by a fixed porous plate 5, free from revolution, and descend, and this flow is repeated (direction of flow is shown by the arrow (a)). Accordingly, the content articles are sufficiently stirred, and polished.