Cerium Oxide is a versatile polishing compound that can be used for polishing a wide variety of stones and even glass. Standard Cerium is a more forgiving grade of Cerium, the larger particle size allows users to achieve a polish with difficult to polish stones. One of the best all purpose polishes, cerium will polish quartz, agate, opal, obsidian, etc. Cerium is the perfect starter polish and will not break the bank. All Cerium grades work best with leather for stones, and felt for glass. Simply mix the polish with a little water to create a thin paste and apply generously to polishing surface. Use minimal water to keep the piece cool, and prevent washing away of good Cerium during polishing. If Cerium is not polishing with the desired effect, Tin Oxide is the next polish of choice, then Linde-A-Polish for very difficult stones.