To efficiently remove the dust or labels by putting the glass cullet and the cleaning water in a rotary container, and turning and stirring them to clean the glass cullet and to chamfer an edge.

When a rotary drum containing the glass cutlet and the cleaning water is tuned for, e.g. 10-15 minutes, the glass cullet is stirred by the rotation of the rotary drum and the rotation of a stirring blade 11 and a resistance blade 12. As a result, the sharp edge of the glass cullet is worn by the friction when the glass cullet slides down the resistance blade 12, the sliding movement between the glass cullet, or the sliding movement of the glass cullet with an inner wall of the rotary drum, the stirring blade 11 or the resistance blade 12, and the glass cullet is chamfered in a curved condition. Foreign matter such as a label attached to the glass cullet is separated from the glass cullet.