No need to stop and clean these stones as you polish—they’re filled with oil to keep debris from getting stuck in the pores. Use a holder to polish by hand or with a power tool (both sold separately). You’ll also need a water-soluble or oil-based lubricant to wash away debris and reduce friction and heat on your workpiece.

Aluminum oxide stones, also known as India stones, scrape away material slowly to give you more control over how much material you take off. They are good for the final stage of polishing.