The stuff you place in the tumbler specially to shine the rocks in the final stage is generally made of cerium oxide, tin oxide, chrome oxide, or aluminum oxide. It's a kind of grit typically called a polishing compound and is extremely good. You use the best grit, five hundred, https://www.facebook.com/permalink.php?story_fbid=pfbid071ZD76TNLYkPybEVNBWHVy3Ka1UJ8AjzzXjpssAusvfqdMEPBEF86Uv2XhdjMPRJl&id=61562415773754&__cft__[0]=AZUWBtn_Dehxt3fTOXyTXs2NGXckR0geuLTrSa8o7_2wfLVx93WzxYqlHyvwG6KCBIdchsELML05LH7oyJyMaVoo0ElmjZet94afZmnkUS68yo0N5erDEshVM1YhGc6W8HOKt0kZaCOd1FKUDA2qtjY1o2O2paiab0HRiv3IW2dR7KUizwd2vqAIFcE_7FqzBumLObpxmHMxj5MkOl9ghy52&__tn__=%2CO%2CP-R