22 Best Rocks For Tumbling & What To Look For

If you’re wondering what the best rocks for tumbling are then you’ve found the right article! In this article, not only will you find out the best rocks for beginners, we’ll also go through more and more challenging rocks for those who want to sink their teeth into something new!

And just remember, the key with all of these rocks is to be patient, learn from your mistakes, and keep working until you get your rocks coming out perfect!

While I am still fairly new to the hobby I’ve had a lot of success (and a few failures). With this in mind, here are my top rocks to tumble!

Best Rocks For Tumbling (Beginner Friendly)

If you’re just starting out, then any of the following are going to be a great choice for you to tumble! I personally love how aventurine and jasper look when they’re finished tumbling! However, of course, whichever one you choose will look beautiful!

Rock TypeMohs HardnessQuick Take
Agate6.5-7Versatile and durable, comes in various colors and patterns.
Amethyst7A stunning purple quartz that’s hard and durable.
Aventurine6.5-7Known for its shimmering effect; use finer grit for best results.
Carnelian6-7Warm, reddish-orange color that pops when tumbled.
Clear Quartz7A blank canvas that turns ethereal when polished.
Howlite3.5Soft and porous; requires extra care but offers a marble-like appearance.
Jasper6.5-7Intricate designs and durable enough for tumbling.
Rose Quartz7Soft pink hue symbolizing love; hard and durable.
Tiger’s Eye7Known for its unique chatoyancy; durable and mesmerizing.

Agate

Mohs Hardness: 6.5-7
Agate is a one of the most popular rocks to tumble and with good reason. With a Mohs hardness of 7, it’s durable enough to withstand the tumbling process. Plus, agates come in a kaleidoscope of colors and patterns, offering a visual treat once polished, thanks to how bright it comes out. If you’re looking for both versatility and durability, agate is your go-to.

Amethyst

Mohs Hardness: 7
Amethyst, with a Mohs hardness of 7, is like the crown jewel of the quartz family. It’s not just stunningly beautiful with its purple hue, but it’s also hard and durable, making it ideal for tumbling. The end result is a gem-like finish that’s sure to impress.

Untumbled Amethyst

Aventurine

Mohs Hardness: 6.5-7

Aventurine has a Mohs hardness of 6.5 to 7, making it slightly softer than some other minerals. It’s known for its shimmering effect called aventurescence. Because of its softer nature, opt for a finer grit and shorter tumbling times to get the best results.

Untumbled Green Aventurine

Carnelian

Mohs Hardness: 6-7
Carnelian, having a Mohs hardness between 6 and 7, is a close cousin to agate. What sets it apart is its warm, reddish-orange color that really pops when tumbled and polished. It’s a hardy mineral, so it holds up well in the tumbler.

Clear Quartz

Mohs Hardness: 7
Clear quartz, with a Mohs hardness of 7, is like the blank canvas of the mineral world. Its incredible hardness makes it a good candidate for tumbling. The beauty of clear quartz lies in its ethereal, crystal-clear appearance once polished.

Untumbled Clear Quartz

Howlite

Mohs Hardness: 3.5

Howlite is notably soft, with a Mohs hardness of just 3.5. It’s a porous mineral that requires extra care during the tumbling process. However, with that being said if you use a very fine grit and keep the tumbling times short to maintain its integrity, and add it with other softer rocks, you’ll have no problem! And of course, its marble-like appearance can be a unique addition if you’re up for the challenge.

Untumbled Howlite

Jasper

Mohs Hardness: 6.5-7
Jasper, with a Mohs hardness ranging from 6.5 to 7, is another member of the quartz family but stands out for its patterns and colors. From speckled to striped, jasper offers intricate designs and is durable enough for tumbling.

Untumbled Red Jasper
Untumbled Black Jasper

Rose Quartz

Mohs Hardness: 7
Rose quartz, also scoring a 7 on the Mohs scale, is the epitome of love and beauty in mineral form. Its soft pink hue is eye-catching and symbolizes love and harmony. Like its quartz relatives, it’s hard and durable, making it a good candidate for tumbling.

Untumbled Rose Quartz

Tiger’s Eye

Mohs Hardness: 7
Last but not least, tiger’s eye, with a Mohs hardness of 7, is known for its unique chatoyancy or cat’s-eye effect. This rock offers a mesmerizing, silky luster when tumbled and polished and is durable enough to handle the tumbling process.

Untumbled Tigers Eye

A Little Bit Harder

While these stones are a tad harder to polish, with the right care, you should have no problem getting them through the tumbling process! Just remember, you should only add stones that are around 1-1.5″ in length to your tumbler, and if possible you should try to add stones with similar hardness.

Rock TypeMohs HardnessQuick Take
Amazonite6-6.5Beautiful blue-green color but slightly softer.
Blue Apatite5Delicate but rewards with a shiny, smooth texture if tumbled carefully.
Sodalite5.5-6Deep blue color; use finer grit and be cautious as it can be brittle.

Amazonite

Mohs Hardness: 6-6.5

With a Mohs hardness of 6 to 6.5, Amazonite is on the softer side. Its beautiful blue-green color can add a unique touch to your collection. While it’s still quite hard compared to other gems, it does have planes of cleavage, increasing the risk it will break if it’s hit too sharply.

Blue Apatite

Mohs Hardness: 5
Blue apatite, has a Mohs hardness of 5, so remember it may not do as well if it’s put with harder stones. And while it’s delicate nature can make it harder to tumble with harder stones, if you can get it through the tumbling process, you’ll be rewarded with a beautiful shiny, smooth texture!

Untumbled Blue Apatite

Sodalite

Mohs Hardness: 5.5-6

Sodalite, with a Mohs hardness of 5.5 to 6, is another softer mineral. It’s known for its deep blue color, often mixed with white calcite. Given its lower hardness, you should use a finer grit, and you should also be aware that sodalite can be brittle, so make sure you don’t overtumble it.

Untumbled Sodalite

Hard To Tumble

These are the stones that are generally considered hardest to tumble. If you plan on tumbling these ones, you’ll need to go through more trial and error than the other ones. So be patient with yourself until you get the exact timings perfect!

Rock TypeMohs HardnessQuick Take
Dalmatian Stone5-7.5Tricky due to mixed hardness levels; porous and needs caution.
Green & Rainbow Fluorite4Brittle and may contain harder minerals; proceed with caution.
Lapis Lazuli5-5.5Soft and brittle; contains harder minerals that may cause chipping.
Labradorite6-6.5Prone to chipping; challenging but offers iridescent look when polished.
Malachite3.5-4Soft, brittle, and porous; needs thorough rinsing and careful tumbling.
Moonstone6-6.5Brittle and sensitive to temperature; use plenty of ceramic media.
Onyx6.5-7Surprisingly brittle; reduce tumbling time and use plenty of ceramic media.
Obsidian5-5.5Volcanic glass that chips and bruises easily; extreme care needed.
Petrified Wood7-8Hard but porous; needs thorough washing before each tumbling stage.
Sunstone6-6.5Prone to fracturing; use plenty of ceramic media and reduce tumbling time.

Dalmatian Stone

Mohs Hardness: 5-7.5
Dalmatian stone is a mixed bag, comprised of quartz and feldspar, which have different hardness levels. This means it can some times be tricky to tumble without damaging parts of the stone. Dalmatian stone is also fairly porous so so it’s best to tumble it with caution.

Untumbled Dalamatian Stone

Green Fluorite & Rainbow Fluorite

Mohs Hardness: 4
While green and rainbow fluorite are possible to tumble, you are going to have a much harder time doing so. With a combined Mohs hardness of 4, and a brittle nature, caution must be taken if you plan to tumble these rocks.

On top of this, fluorite can occasionally contain quartz or calcite which is a lot harder than fluorite, which could end up causing damage during the tumbling process.

Untumbled Green Fluorite

Lapis Lazuli

Mohs Hardness: 5-5.5
Like others on this list, Lapis Lazuli has a softer hardness compared to other easier rocks. On top of this it can also be quite brittle, and the fact that pyrite and calcite are found inside it (which are harder) means you could end up with chips in your stones when the tumbling process is complete.

Untumbled Lapis Lazuli

Labradorite

Mohs Hardness: 6-6.5
Labradorite, has a Mohs hardness of 6 to 6.5, and is also prone to chipping. One of the biggest things to remember about labrodorite is that what makes it so beautiful is its labradorescence, which gives it an iridescent look once polished. If you’re new to tumbling, then labradorite will definitely be a challenge to tumble.

Malachite

Mohs Hardness: 3.5-4
Malachite is difficult to tumble for a number of reasons. It has a Mohs hardness of 3.5 to 4, making it quite soft. As well as this, it’s quite brittle and can be easily damaged. And if that wasn’t enough, malachite is also a porous rock, so if you do plan on tumbling it, make sure to rinse it thoroughly to remove any grit during each stage.

While it’s still possible to tumble malachite, more planning will need to go into it, and be ready for more mistakes as well!

Moonstone

Mohs Hardness: 6-6.5
Moonstone, has a Mohs hardness of 6 to 6.5. It’s also another brittle rock, so if you don’t cushion it enough, you’ll either end up breaking it or scratching it. Another thing to note, is that moonstone is also susceptible to temperature change. While this should be fine when you’re tumbling, it’s still something to keep in mind!

Fortunately, if you’re adding plenty of ceramic media to the tumbler, and making sure you aren’t tumbling it for too long. Moonstone will come out looking fantastic!

Onyx

Mohs Hardness: 6.5-7
Onyx, although a form of chalcedony with a Mohs hardness of 6.5 to 7, is surprisingly brittle, which means a lot of care will need to be taken when tumbling it. Again, your best chance of tumbling onyx successfully is to decrease the amount of time you put it in the tumbler, and make sure that you’re using plenty of ceramic media.

Obsidian

Mohs Hardness: 5-5.5
Obsidian, with a Mohs hardness of 5 to 5.5, is volcanic glass that chips easily. If you do plan on tumbling obsidian, extreme care is needed. Not only will it chip, but it can also bruise as well. When bruising occurs you’ll notice fractures and cracks where the obsidian was hit by other rocks.

You can choose to bypass the course grit and go straight to the second stage of polishing if you want to increase the chance of a successful polish.

Untumbled Obsidian

Petrified Wood

Mohs Hardness: 7-8
Petrified wood, despite having a Mohs hardness of 7, can be difficult to tumble. The main reason for this is because it can be extremely porous, which means you’ll need to wash it thoroughly before each stage of tumbling.

Sunstone

Mohs Hardness: 6-6.5
Sunstone, with a Mohs hardness of 6 to 6.5, is prone to fracturing because it tends to have lots of planes of cleavage. If you’re planning on tumbling sunstone, make sure you’re using plenty of ceramic media, and try to reduce the amount of time you keep it in the tumbler.

What To Look For When Choosing Rocks To Tumble

Fortunately, you don’t just have to take my advice on what rocks you should tumble, when choosing rocks to tumble, there are a few things you can look for which will help show you how easy or difficult it’s going to be!

Hardness Between 6-8

When it comes to rock tumbling, hardness is a crucial factor. You’ll want to aim for rocks with a Mohs hardness between 6 and 8. Rocks that are too soft will break down quickly, and those that are too hard may not polish well. The sweet spot is between 6-8, where you’ll get a rock that’s durable yet receptive to polishing.

However, just because a rock isn’t between 6-8 on the hardness scale, it doesn’t mean you can’t use them! Just make sure you’re using more ceramic media, and that you’re adding rocks of a similar hardness.

Unfractured Rocks

You’ll want to avoid rocks with fractures or cracks. These imperfections can cause the rock to break apart during the tumbling process, ruining your batch and wasting time and resources. So, make sure to inspect each rock carefully.

If you do notice that a rock is fractured, all is not lost. Just break it at the fracture, and if the pieces are still big enough then you can put them into your tumbler. On the subject of size…

The Correct Size (½” – 1 ½”)

Size matters in rock tumbling. Aim for rocks that are between ½” and 1 ½” in size. Too small, and they might get stuck in your tumbler. Too big, and they won’t tumble properly, leading to uneven polishing. Think of it as the Goldilocks principle of rock tumbling: you want rocks that are just right in size.

However, with that being said, I have had success with rocks that are smaller than 1/2 an inch in size, so if you do have smaller rocks, all is not lost.

Smooth Rocks (Optional)

Smoothness is another key aspect to consider. The smoother the rock, the less time and grit you’ll need to get a polished end result. So, when you’re out there hunting for rocks, keep an eye out for those with a naturally smooth surface. It’s like giving yourself a head start in the tumbling process!

How To Test If A Rock Can Be Tumbled

If you’re still not sure whether a rock can be tumbled or not, here are a few of my favourite ways to test whether they can.

  • Scratch The Rock With A Nail: If I want to test the hardness of a rock, I’ll try to scratch it with a nail. If the nail can scratch the rock, then it could potentially be too soft for my tumbler. While I’ll still chuck it in, I won’t be as hopeful with my results.
  • Check It’s Density: I also check the density of the rock as well. To do this I just drop it into a bowl of water. If I notice that it sinks, then I know it can handle the tumbler.
  • Visual Inspection: And lastly, I’ll also visually inspect the rock. When you visually look at the rock you’ll often notice weaknesses and points of fracture. All you have to do then is crack the rock in these areas before putting it into your tumbler.

More Top Tips For Tumbling Rocks:

  • Choose a variety of rocks in different shapes, sizes, and colors to create a more interesting tumbled batch.
  • Clean the rocks thoroughly before tumbling to remove any dirt or debris.
  • Use a rock tumbler that is the appropriate size for the amount of rocks you are tumbling.
  • Follow the instructions that come with your rock tumbler carefully.
  • Be patient! Rock tumbling can take several weeks, depending on the type of rocks you are tumbling and the desired results.

Recap

Now you know all the best rocks to tumble! Again, I’d personally recommend aventurine and jasper if you’re just getting started, but with patience trial and error, I’m sure you’ll have great success no matter what rocks you choose!

If you liked this article, make sure you check out the rest of the website! Otherwise, have a great day!

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The Rock Tumbler

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