Rock Tumbling

Rock tumbling, known technically as tumble finishing, is a technique for smoothing and polishing rough stones by rotating them in a barrel together with abrasive grit, commonly silicon carbide, and a liquid such as water, in a process that mimics how the sea naturally polishes beach pebbles and sea glass. A simple barrel or rotary tumbler is the cheaper, more common approach, while a vibratory tumbler works roughly twice as fast at greater cost; either way a full polishing run takes several weeks and moves through progressively finer grits before a final polishing stage. Small home rock tumblers were an especially popular hobby item in the 1970s, and hobbyists still use them today to turn ordinary stones into polished gems, alongside industrial operators who use larger versions of the same equipment for professional finishing work. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/