Polishing Marbles in a Rock Tumbler
Step 1. We sand the marbles in a Lot-o-Tumbler or a Thumler's UV-10 for a few hours to a couple of days depending upon the depth of the chips and scratches on the marble. We use 150/220 silicon carbide grit as an abrasive with a small amount of water. Small scratches and chips are removed in a few hours.