A Northern Michigan favorite, Petoskey stones can be found in virtually every souvenir shop this side of the Toledo Strip. It’s really nothing to buy a couple of polished stones and toss them in with your sea glass and agates, but you can do one better: exercise that good ol’ Midwestern work ethic and search for your own Petoskey stones straight out of the Great Lakes, then polish them yourself. So grab some stones and make a day of it (Really, you’ll need the whole day!). Here’s how to polish Petoskey stones.

Rock Polishing Supplies:

  • Petoskey stone – Spend a morning sifting through the colorful stones that blanket the beaches of the Great Lakes (especially those along Lake Michigan). Wet the stone to be sure it’s a Petoskey. If you’ve got the right sort, a dotted honeycomb pattern will surface. Some shops sell unpolished Petoskey stones if you’re not up for the hunt.
  • 220-, 400-, and 600-grit sandpaper – You’ll find all of these at your local hardware store. Choose a variety that still works when wet.
  • A file – This will only be necessary if you choose to round or reshape your stone. We didn’t.
  • A towel or several layers of newspaper
  • A piece of corduroy or velvet fabric – We used red velvet and found that our stone was stained from the dyes in the fabric. Choose a more neutral-toned fabric to avoid this.
  • Polishing powder or compound – You can purchase products made specifically for rock polishing like we did, but many car-finish rubbing compounds will work just as well.
  • A container of water – A bowl or small basin will do. You’ll need to empty and refill your container with clean water several times throughout the process.

How to Polish Petoskey Stones:

  • Some like to give their stones a bit of rounding off, so first, you can use the file to shave the stone into your desired shape. Maybe its lumps give your stone character, so it’s okay to skip this step like we did.
  • After your stone has been shaped, begin sanding your damp stone with the 220-grit paper. This sandpaper is the roughest of the three and should be used to rid the stone of any obvious scratches or unsightly patches. Rub the sandpaper against the stone in a steady, circular motion until the stone’s whole surface has been sufficiently scoured. This first sanding is the most important and should be performed thoroughly. This stage of sanding took us the longest and could take you several hours. Rinse and dry the stone, then replace your water.
  • Repeat this process using the 400-grit sandpaper to work out any scratches left by the 220-grit paper. Rinse and dry.
  • Finish sanding with the 600-grit paper. When you think you’ve done a thorough job and the stone looks and feels smooth, rinse and continue sanding for five-to-ten minutes.
  • Examine the stone for any remaining scratches and work all of these out before you stop sanding. You won’t want to polish your stone until all scratches and abrasions are gone.
  • Apply a small amount of polishing powder or compound to your piece of corduroy or velvet, then use the fabric to work the polishing product into the stone in a circular motion like the one you used while sanding. When you’ve thoroughly polished the stone’s entire surface, wipe it with a clean, dry cloth.
  • Finally, admire your handiwork, and find a special place on your shelf to display your hand-polished Petoskey stone! This was our favorite part.

**Keep in mind, it’s illegal to take stones from national parks or lakeshores such as Sleeping Bear Dunes and Pictured Rocks. If you’re rocking hunting on state-owned land, you cannot remove more than the aggregate total weight of 25 pounds, per individual per year of any rock, mineral specimen (exclusive of any gold bearing material), or invertebrate fossil for individual or non-commercial hobby use.

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Photo(s) by Emma Winowiecki