The things you set into the tumbler specifically to polish the rocks in the ultimate phase will likely be made of cerium oxide, tin oxide, chrome oxide, or aluminum oxide. It is a form of grit historically called a polishing compound and is extremely good. The primer acts as a https://www.facebook.com/permalink.php?story_fbid=pfbid0pJKGgRvVTsfTCtJ5tak6SUJ5ymgDetxzjcgW6kEiTpAqgHasCi2doykziDdLBxVBl&id=61562415773754&__cft__[0]=AZV964PfkhTubvAMf2bTV1XhNBUUD2Vg-F7bLhy7GWl7zj1onQbBObHNkuvws4QUTstxSG8tJHvPu2i75NOHj9zgd4OHn0QvWLuR3-J-NN5qO5GluG5mTMBNXNvy_sY_CHjeRzSU_LGsDLKF1cvaLTMLq1lm8qe6o41LucAUqCX9nVZpW4UxcRu-y78djF1vwg_u3f2vPQpMFB3Au-4_Ovry&__tn__=%2CO%2CP-R