The things you put into the tumbler especially to polish the rocks in the ultimate phase will likely be made of cerium oxide, tin oxide, chrome oxide, or aluminum oxide. It's really a form of grit historically referred to as a polishing compound and is amazingly wonderful. When working with https://www.facebook.com/permalink.php?story_fbid=pfbid02M3pzSNhRs3pYNi8TrH5kEbpVmTNxMFUWpQBP8w3XJUcJy1bwKkPGxEg1Ck1cB8vWl&id=61560512640678&__cft__[0]=AZWImNtQj8D89AUGxg60JG4mCqOvBFcgVC_YGPylERzWhz1_PvNqY3NN3q6xCHwK5gm5J69AQ_uDY5mKKeAXVvowAA8nfq1FXdzqw_pl8WO1H89mnKMy_8JIVA_mTv-1HZXjWfhrePyYN8IN2dcqwha-x4G3-9M2AlyiqVoTkhY4TuTA0G6T2molbK0z22dJnEf9wHQInQvfDMnHY3nQqKLd&__tn__=%2CO%2CP-R