For an avid rockhound or lapidarist, few activities are as rewarding as finding the perfect stones in nature to tumble into polished gems. A world of tumbling potential lies right underfoot if you know where to look. Getting out into nature and searching for rocks is a fun adventure that often yields amazing results.
Many excellent rocks for tumbling can be found along hiking trails, in streams, on beaches, at construction sites, or along road cuts. The key is looking for rocks that exhibit qualities like smoothness, hardness, interesting colors and patterns. Stream-tumbled rocks are often ideal since they have been naturally smoothed by the flowing water. Construction sites and road cuts allow you to peek at the geology and find newly exposed rocks. Part of the joy is never knowing what beautiful stones you might uncover.
However, it takes knowledge and experience to identify rocks with good tumbling potential. Beginners should educate themselves on rock properties before setting out to choose tumbling stones. Hardness, durability, texture, color, and uniformity are all key factors. Quartz, agate, jasper and other hard, dense rocks with smooth textures tend to yield the best polished results. With practice, anyone can become skilled at recognizing rocks that will tumble into dazzling gems. The trick is being able to spot potential even in a roughly textured stone plucked from a hiking trail or streambed.
Characteristics of Good Tumbling Rocks
Most rocks you find in nature are not good for rock tumbling. They are either too dull on the outside, such as shale or mudstone; they will degrade in a rock tumbler, or their sharp edges and points make them dangerous to tumble.
Don’t worry if you can’t find rocks in these exact specifications. Almost any rock can be polished using the tumbling process and most types of stones work well for tumbling. Just keep in mind that different stones will require varying degrees of polishing and work best with certain types of rocks.
Hardness
Soft rocks can be very difficult to polish and usually do not produce the desired results. You should always try to pick out rocks that are at least somewhat hard, like granite or quartzite, when you’re looking for good tumble stones.
The Mohs scale is a way of measuring how easily different minerals scratch other materials and one another. Those with a Mohs Hardness between about six and eight work best for tumbling while softer minerals, like talc or gypsum, can be difficult to polish.
You should avoid rocks that have been weathered too much because they often lose their sharp edges and points from years outside.
Density
Pore spaces trap particles of grit that hit the rocks, ruining the polishing process. Rocks with big pores or low density are not recommended for tumbling because they produce poor results and waste time and money on stones that you cannot use. A good rule of thumb is to pick out dense rocks with smaller pore spaces; these will polish quickly in a rock tumbler without a lot of work.
Fractures
Rocks with fractures will spoil the polishing process by trapping grit in the cracks and breaking parts of your stones into tiny pieces. That is why you should always try to avoid rocks that have a lot of fractures or are covered with seams filled with dirt; these will produce poor results when they come out of your rock tumbler.
It is okay to pick out rocks with minor cracks or fissures because they can be repaired after tumbling using epoxy glue and a bit of patience.
Texture
Rocks that produce granular debris when rubbed together will not polish well in a rock tumbler. You should always try to pick out rocks with smooth surfaces and avoid those that produce a lot of dust or granules when they are rubbed together.
For your stones to polish efficiently, you’ll need as many sharp edges as possible. Rocks without ridges or jagged points will make it difficult to shape your stones.
Color
Just make sure you pick out rocks that are colorful and vibrant because this will help your finished stone stand out from the rest in a display case or on a shelf.
If you want to create an interesting visual effect with two different colors of stones, check for rocks that have similar patterns or coloration at opposite ends of the rock. This way, when you put them in your tumbler together they will produce a neat color-swirling effect as they tumble around each other.
Your stones don’t need to be uniform colors throughout but should have some contrast between different parts of the stone that creates an interesting visual appearance.
Cleanliness
Always try to pick out rocks that are as clean and dry as possible because any bits of moisture, oil, grease, or other substances will contaminate the polishing grit in your rock tumbler. This can also transfer chemicals from one stone to another during the tumbling process.
Size
Size is not as important as shape and hardness but you should still try to pick out rocks that are about an inch thick because those will tumble the best. Your stones should also be about an inch wide to fit into your rock tumbler barrel easily; if they are too small, it can be difficult or frustrating when you try to load them into the machine. If stones are too big, they won’t fit into the barrel at all.
Best Rocks for Tumbling
- Granite: a hard and dense rock that is good for polishing and comes in many different colors
- Quartz: another hard, durable stone with plenty of color options
- Jasper: has beautiful patterns on its surface when polished
- Feldspar/Quartz Family Rocks are the most popular rocks to tumble because they are known for producing wonderful results.
Other popular types of rocks for tumbling include tourmaline, obsidian, citrine, amethyst, and petrified wood.
Using a Rock Tumbler: An In-depth Look
This process of tumbling rocks can be fascinating, especially when you have the best rock tumbler at your disposal. It’s like a magical machine that transforms rough rocks into shiny and smooth gems. The key to using a rock tumbler effectively is understanding its operation and making the best use of the rocks you can find.
Where to Find Rocks for Tumbling in Nature
One of the best places to find rocks suitable for tumbling is right in nature. Riverbeds and beaches are ideal spots to look as the moving water has already naturally tumbled many stones smooth.
When searching for tumbling stones in nature, keep an eye out for rocks with the characteristics mentioned earlier. Focus on ones that are hard, dense, and free of major cracks or cleavage planes. Smooth, rounded rocks that have been naturally tumbled tend to tumbling these stones again quite well.
Rocky outcrops and cliffs also offer lots of tumbling potential. Look for pieces that may have weathered off or collect chunks that you can easily rock to break into smaller pieces. Any section exposed to the elements is a good place to poke around.
Avoid shale or crumbling rocks as these will likely not tumble well in a rotary tumbler. Test unknown rocks for hardness by scratching with a knife or trying to chip off a small edge.
Make sure to seek permission if collecting rocks on private land. Only take what is reasonable for personal use. With some searching, you can uncover amazing tumbling treasures offered freely by nature.
Picking Your Rocks for Tumbling
When selecting rocks for your tumbler, you have to pay attention to certain characteristics. Hardness of the rocks plays a crucial role. Softer rocks may break down too much during tumbling and may not yield the polished gems you desire. So, when you find rocks to tumble, ensure they have a hardness of at least six on the Mohs scale.
Rocks that are too soft or have an abundance of fractures don’t make the best rocks to tumble. If you tumble these, you’ll likely be left with a lot of rock dust and debris. Your goal is to create a beautiful rock collection, not a pile of rock crumbs!
When you use rocks in a rock tumbler, you need to consider the size as well. The rocks shouldn’t be so large that they take up too much space in the tumbler. Ideally, for every pound of rock, there should still be enough space for water and grit to move freely.
Sorting and Preparing Your Rocks
Before adding rocks to your tumbler, sort them by hardness and size. This helps to ensure that similar rocks tumble together, preventing the harder ones from damaging the softer ones. It’s perfectly fine to tumble rocks of different colors and types together, as this won’t affect the final polished result.
Sometimes, rocks come in sizes too big for your tumbler. You might need to break the rocks by hand into smaller pieces for tumbling later.
When preparing your rocks for the tumbler, remember, the goal is to get your rocks smooth and shiny, not broken into tiny pieces. It’s also essential to clean your rocks every time before you start the tumbling process to prevent grit contamination.
The Art of Tumbling
Once you’ve selected and prepared your rocks, it’s time to start tumbling. The duration for which you tumble your rocks will depend on their hardness and your desired level of polish. Remember, some rocks don’t take as long to polish as others, so keep an eye on them.
It’s also important to note that some rocks aren’t suitable for tumbling. You don’t want to tumble rocks that are heavily weathered, overly porous, or crumbly. These will not withstand the tumbling process and will not result in the beautiful, polished stones you’re hoping to add to your collection.
Always remember that the art of rock polishing is a process of patience and persistence. So don’t be disheartened if your rocks don’t come out perfect the first time. Keep learning, keep tumbling, and soon you’ll be an expert at choosing the best rocks for rock tumbling.
| Steps | Description | Tips |
|---|---|---|
| 1 | Selecting Rocks | Choose rocks with a hardness of at least 6 on the Mohs scale. Avoid overly soft or crumbly rocks. |
| 2 | Preparing Your Rocks | Clean and sort your rocks by hardness and size before adding them to the tumbler. |
| 3 | Tumbling Rocks | Start the tumbling process in your rock tumbler. Monitor the progress regularly to ensure optimal results. |
| 4 | Post-Tumbling | After tumbling, clean your rocks thoroughly to remove any grit. Now, you’re ready to admire your shiny, smooth gems! |
Enjoy the exciting world of rock tumbling, and remember, practice makes perfect. Don’t be afraid to experiment and learn from your experiences. Happy tumbling!
A Detailed Guide on Rock Hunting for Tumbling
In the process of rock tumbling, it’s vital to start with the right kind of rocks. Choosing the right rocks and minerals is the first step towards achieving a beautifully polished collection. So, how does one find good rocks for tumbling in nature? This guide will aid you in this quest and help you understand the rock tumbling process.
Step 1: Identifying Suitable Rocks for Tumbling
Not all rocks can be tumbled. Many rocks you find in nature might not be suitable for tumbling due to their softness, or they might degrade in a rotary tumbler. Some common types of rocks suitable for tumbling include igneous rocks like granite and metamorphic rocks like quartz. However, rough rocks with a gritty texture, despite being hard, are not ideal as they may not yield a smooth polish.
One of the best places to find good rocks for tumbling is along riverbeds, where river rocks often have been naturally tumbled, resulting in smoother rocks. Rock hunting in nature can be an adventurous task, as you will come across a variety of rocks. Nature-tumbled rocks often give the best results.
| Types of Rocks | Tumble-Ready | Why or Why not |
|---|---|---|
| Igneous rocks (Granite) | Yes | They are hard and can hold a good polish |
| Metamorphic rocks (Quartz) | Yes | Hard and shiny, great for tumbling |
| Sedimentary rocks (Limestone) | No | Usually too soft, may crumble in the tumbler |
| Soft, gritty rocks | No | These rocks won’t hold a polish |
Step 2: The Rock Tumbling Process in a Vibratory Tumbler
A vibratory tumbler is an efficient and fast tool to polish rocks. It works by vibrating the rocks against each other and against the tumbling media to smooth and polish them. The tumbling barrel needs to be filled correctly; the general rule is to fill the tumbling barrel about two-thirds to three-quarters full of rocks. Make sure the rocks are of similar hardness to ensure even tumbling.
Step 3: Preparing Your Rocks for Tumbling
Before adding the rocks to the barrel, you should sort them by hardness and size. Rocks of similar hardness should be tumbled together to prevent the harder rocks from damaging the softer ones. Large rocks might need to be broken down into smaller sizes to fit in the tumbler.
Step 4: Selecting Tumbling Media
Tumbling media is a crucial component of the rock tumbling process, and it’s often added to the tumbling barrel along with the rocks. It serves multiple purposes: it helps to polish the rocks, and it prevents them from knocking into each other too harshly, which could cause them to chip or break. The type of tumbling media you choose depends on the stage of rock tumbling you’re at and the type of rocks you’re tumbling.
Step 5: Post-Tumbling Care
After tumbling, the rocks should be thoroughly cleaned before they are used or displayed. They might require multiple washes to remove all the grit. Now, you’re ready to display your beautiful rocks!
| Step | Task | Tip |
|---|---|---|
| 1 | Identify suitable rocks | Look for hard rocks along riverbeds |
| 2 | Understand the tumbling process | A vibratory tumbler is efficient and quick |
| 3 | Prepare rocks | Sort by hardness and size |
| 4 | Select tumbling media | Choose based on the rock type and tumbling stage |
| 5 | Post-tumble care | Clean thoroughly to remove all grit |
While rock tumbling is a patience-testing process, the end result can be greatly satisfying. Starting with a beginner’s guide to rock tumbling, you’ll soon find yourself enjoying this hobby, eager to explore more varieties of rocks to collect and polish. Remember, practice makes perfect. So, don’t get disheartened if you don’t get the best results the first time. Keep tumbling!
Pro Tips: Buy Your Rocks
If you’re having trouble finding rocks for tumbling or don’t have enough rocks, you can always buy tumbling rough or batches of rocks online. Looking for the best rocks online can save time and effort, and you can select from a wide range of rocks best suited for your needs. The best place to buy rocks for tumbling would be a reputable online gemstone or mineral store. Always look out for a well-rounded tumbling recipe, to ensure you get interesting rocks that will result in a diverse and beautiful collection.
Remember, whether you are searching for rocks in nature or buying them online, your goal is to enjoy tumbling and create a collection of polished rocks that you love. Happy tumbling!
FAQs
When should I tumble my stones?
You will want to start tumbling them as soon as possible after you pick them out of the ground or river. Rocks with high moisture content can contaminate your polishing grit and damage your tumbler barrel; this is why it's important to find rocks that are dry whenever possible.
How long should I tumble my stones?
If you are using commercially manufactured grit, it's recommended to run your rocks in the tumbler for at least one week to get good results. This can vary depending on what kind of stone you are working with and how muddy or dirty they were when you first picked them out.
How many times should I run my stones in the tumbler?
It depends on how badly your stones are contaminated with dirt or mud; you will want to run them through at least three cycles of polishing grit before they come out clean enough for use. If your rocks have particularly high moisture content, you may need to run them through five cycles before you are satisfied with the results.
Can I leave my rocks in a rock tumbler forever?
If you want to keep your rocks looking their best, it's recommended not to leave them in a rock tumbler more than two months at a time. The very hard quartz and feldspar family of rocks can be left in longer but will still benefit from a break now and then.
Final thoughts
Picking out the right tumbling rock can be a difficult task. You need to consider things like color, shape, texture, and hardness when picking them out for your project. The guide below will help you pick out the perfect stones from all of those piles at your local stone yard or rock store so you don’t have to worry about it anymore! After reading this article on the characteristics of good tumbling rocks, now is the time to find that perfect piece for your next project. Which one are you going to choose?
Tired of picking rocks for Tumbling? Start from Sea Glass!
Hello John
I was thinking that I would like to pick up “rocks” while traveling and then tumble them to make them pretty and showable. Do all rocks polish up nicely (and I understand the soft rocks and hard rocks) but do all rock have color to show pretty or will some always just be rocks?
Hello D. Hess
Answer:
It really depends on the type of rock. Some rocks, like granite, have a natural sheen and don’t even need to be polished. Other rocks, like limestone or ruby, can be polished to a high shine and will take on a variety of colors depending on the polish used. So it really just depends on the individual rock and what type of finish you’re looking for.
That being said, I highly recommend trying it out yourself! It’s really cool to see the different results you can get with just a little bit of effort.
[email protected],,,,,hello D.hess. I polish my rocks, starting with 200 grit then double that number up to 1000, and then double that to 2000 grit. the 2000 grit I use is a car clearcoat polish that removes scratche for the clearcoat on your car. it is amazing. it is also the method of polishing gelcoat on a boat. It cost about 20 dollars for the bottle of liquid grit, but believe me, my method will beyond amaze you, ONE WEEK PER GRIT.
Hi, Alan.
Your polishing method is quite intriguing! It’s essential to use the proper grits to achieve a high-quality finish, and it seems like you’ve got that down pat. However, it’s worth noting that the type of rock you’re polishing can also play a significant role in the final result. Some rocks may require a different approach or different polishing compounds altogether. Also, make sure to clean your rocks thoroughly between grits to avoid contamination and achieve a consistent finish. Happy polishing!