Back in the day, rock tumblers were popular with kids across the U.S. They allowed you to take mundane rocks and turn them into beautiful beaming pieces of jewelry. All you have to do is take a rock, add some abrasive material and turn the tumbler on. A few hours later, Batta bing Batta boom — you have yourself a beautiful polished rock. But what would happen if you put other things besides rocks into the device? And what if you left it on for a whole week?