Ever picked up a smooth, shiny rock and wondered how it got that way?
Maybe you’ve seen those beautiful, polished stones in jewelry shops or in a rockhound’s collection and thought, “I’d love to make that!”
Well, rock tumbling is your ticket to turning rough, raw stones into stunning, polished gems, all in the comfort of your own home.
And it’s easier than you might think!
In this beginner’s guide, I’ll go over everything you need to get started, from the basic supplies to the simple steps that take your stones from rough to shiny.
What is Rock Tumbling?
At its core, rock tumbling is a process of polishing rough stones by grinding them down with abrasive materials in a tumbler (a machine that rolls and tumbles the rocks).
Over time, the constant friction and abrasion smooth out the rough edges and leave the stones looking shiny and smooth.

You start with rough, jagged stones and, after a few weeks, you end up with polished gems.
It’s super satisfying to watch the transformation!
Supplies You’ll Need For Rock Tumbling
So, what do you need to get started? It’s not too complicated, but you do need a few basic supplies to make the magic happen:
- Tumbler
- Rough Stones
- Abrasive Grits
- Water
- Plastic Pellets (optional)
Also Read: Vibratory Vs Rotary Rock Tumblers
How To Rock Tumble
Now that you know what rock tumbling is, let’s dive into how to actually do it.
Don’t worry, it’s not as complicated as it might sound. There are just a few basic steps to follow, and you’ll be on your way:
Step 1: Pre-Tumble (Optional)
Okay, so the pre-tumble is kind of like a warm-up for your stones.
You don’t have to do it, but it can help if your stones are extra rough, jagged, or just need a little extra TLC before diving into the real tumbling process.
During this step, you’ll take your rough stones, add some coarse grit, and run them through the tumbler for a few days.
This helps knock off the big, sharp edges and starts to round them out.
At this stage, you can also sort through your stones and pick out any that are too soft or fragile for tumbling.
Soft stones like limestone or chalk might break apart, so it’s best to avoid those. Harder stones like agate, jasper, and quartz are usually the best candidates for tumbling.
Once you’ve got a nice little pile of stones ready, you’re good to go!
If you decide to skip this, no worries—just start with the coarse grit in Step 2. But if you’ve got some stones that look a little too sharp, the pre-tumble could be a good way to ease them in.
Step 2: Coarse Grit
The coarse grit is your first real grinding stage.
The main job here is to knock down the rough edges and start shaping the stones into something smoother.
Coarse grit is pretty abrasive (60/90 or 80 grit), so it’ll work on the surface of the stones, grinding off the roughest bits. You’ll need to add enough water to make sure everything stays lubricated and the grit sticks to the stones.
If your tumbler’s a little loud, don’t be alarmed—that’s the sound of the grit doing its thing!

This stage typically lasts about 7 days, but you’ll want to check on it after a few days just to make sure the rocks aren’t getting too dry or that the grit hasn’t clumped together.
Also Read: Tips for Choosing a Polishing Kit for Stones
If you see the grit is drying out, just add a little more water.
Also, make sure the stones aren’t all clanking together too harshly. If you’re worried about it, toss in some plastic pellets to cushion the blow.
At the end of this stage, your stones should start looking noticeably smoother.
Step 3: Medium Grit
After your stones have been through the coarse grit, you’re moving on to the medium grit to smooth things out a bit more.
This is when the stones really start to look better—less rough, less jagged.
The medium grit (like 120/220 grit) is finer than the coarse grit but still does a fair bit of abrasion to keep shaping the stones.
You’ll want to tumble the stones with the medium grit for about 7 to 10 days.
You might notice some stones are starting to look more polished while others need a little extra time. If that’s the case, let them go a bit longer.
The medium grit step is all about refining the shape, smoothing out any remaining rough edges from the coarse grit, and prepping them for the fine grit.
During this step, make sure you keep an eye on the water level again.
Sometimes the grit gets used up and can start drying out, so don’t forget to add more if needed.
Also Read: What Rocks Contain Gold?
Step 4: Fine Grit
Here’s where the magic really starts to happen. Fine grit is a game-changer!
At this stage, the stones should be a lot smoother, but you’re now using a very fine abrasive that’s going to refine them even more.
The goal is to remove all those small scratches left by the medium grit, giving your stones that silky, almost glass-like surface.
The fine grit (500 grit) is much smoother than the coarse and medium grits, but don’t be fooled—it still does the job of smoothing out those last little imperfections.
You’ll need to let them tumble with the fine grit for about 7 to 10 days.
Be patient with this step—your stones should be looking really shiny at the end of it, but they’re not quite ready for the final polishing yet.
Sometimes, if you want to get really specific, you can separate the stones into two batches, since some might be more polished than others at this point.
If you’re ready, move on to polishing; if not, give them a little more time with the fine grit.
Step 5: Polishing
Finally, it’s time for the fun part—the polish!
This step is where your rocks go from looking like nice, smooth stones to looking like gemstones you might find in a jewelry store.
For this step, you’ll use a very fine polish, usually a powder like cerium oxide, and combine it with water in the tumbler. The polish will give your stones that final shiny finish and bring out their colors in a way that makes them look absolutely stunning.
This stage usually takes a little longer—about 7 to 10 days again.
It’s the final touch that makes all the work you’ve done so far really shine.
The stones will come out looking glossy and beautiful, with a high-quality shine that you can’t help but admire!
Finishing And Enjoying Your Stones
Once your stones are polished, it’s time to enjoy the fruits of your labor!
You can keep them in a display jar, use them for crafting projects, or even create jewelry out of them if you’re feeling creative. The possibilities are endless!
Some people even turn their polished stones into little gifts for friends and family, or simply enjoy them as part of a personal collection.
It’s also fun to experiment with different types of stones to see how they tumble.
Also Read: What Makes A Great Geode Display Case?
Some stones, like agate and jasper, are known for taking a really nice polish, while others might not shine as brightly.
Either way, it’s always interesting to see how each stone turns out. And honestly, there’s something really satisfying about holding a shiny stone in your hand and knowing you made it that way!
Wrapping Up
Rock tumbling is a fun and relaxing hobby that lets you take rough stones and turn them into beautiful, polished gems.
It’s a simple process that anyone can do at home with the right equipment and a bit of patience. While it does take some time—the results are worth it.
So, if you’re looking for a new hobby to dive into, or if you’ve always wondered how those beautiful polished stones come to be, rock tumbling is definitely worth trying out.
You might just find that it becomes your new favorite pastime!