... grinding ballsProperty: Round grayish silica stoneSize: 2-4cm, 4-6cm, 6-8cm, 8-10cm, 10-12cm, 12-15cmApplication: Silica pebbles can ... a better sea freigth and prompt delivery.5. Negotiable package.6. Negotiable price on large purchase.Japanese customer's test of ... man-made pebbles (round,1-2cm,2-4cm,4-6cm,6-8cm,8-10cm,10-12cm,12-15cm)