Vibrating tumblers do not work in the same way as the rotary tumblers
. These tumblers use high frequency vibrations to create friction between the rocks, and this polishes your stones. These tumblers tend to be even more expensive, although high quality 4lb-capacity tumblers are available for about $120. Polishing in a vibratory tumbler means that the stones stay in the same shape as when they started, rather than becoming rounded. Vibrating tumblers also tend to be quieter than their rotating cousins and polishing is achieved more quickly, and with less grit.