The Stone Circle Rock Tumbling Instructions

Just bought a rock tumbler and don’t know what to do with it? Let’s talk you through it with some rock tumbler instructions.

You cannae beat a guid polish. It just makes your rocks stand out.

<This page contains a few relevant Amazon links. Avoid them by skipping the paragraph entitled “Where to buy replacement rock tumbler grit.”>

We just found out that you guys have been searching for instructions on how to use the new rock tumblers you just bought. Apologies that we haven’t been living up to expectations, but let’s remedy this with a few basic instructions on how to polish rocks mechanically.

Don’t have your rock tumbler yet? Buy rock tumblers or discover what to look for with The Stone Circle.

You Just Bought Your First Rock Tumbler, What Next?

Let’s assume that you have decided which rock tumbler to buy and it has been delivered to you. You have unboxed it and played around with all the little bits that come with it.

Let’s also assume that you have some rocks. If you don’t have rough rocks to tumble, then you can suffer through this quick plug of our own products. Browse our rough rocks by page here or invest in 500g Scottish smoky quartz or 500g of Scottish Jasper to tumble.

We also sell a lapidary mix which is a combination of all of our Scottish rocks. The lapidary mix is for when you know what you are doing. If you insist, though, separate the rocks by type, i.e. we tumble all the quartz (quartz, carnelian, chalcedony, jasper) rocks together and leave out the softer limestone fossils and pink calcite for separate tumbling.

But we are getting ahead of ourselves.

These rock tumbling instructions will talk you through what to do with the rock tumbler and the rocks you just bought.

Rock Tumbling Instructions in Steps

The steps to successful rock tumbling are:

1. Separate rocks by type/choose one type of rock to tumble at a time. This is important because different hardnesses of rock can scratch each other in the barrel. You want all your grit to be controlled.

2. Put your chosen rocks into the rock tumbler barrel. Do not fill it up more than two thirds of the way.

3. Add cold water to the barrel until it just covers the rocks and no more. This is important because you want to create a nice slurry which is thicker than water.

4. Add one heaped tablespoon of grit per roughly one standard sized, 2.5lb barrel. Make sure you use STAGE ONE GRIT, usually F80 or even F60 silica carbide.

5. Put the lid back on the barrel – rubber bit first, then metal bit, then lock with the handle.

6. Put the rock tumbler onto the rollers of your rock tumbling machine. This machine will need oiled once in a while. Keep the oil away from the rubber parts.

7. Set the rock tumbler to one week at the lowest speed setting that you have. Eventually you will be good enough at this to do a five day cycle but start with a seven.

8. Leave it alone for a week.

This all sounds fairly straightforward and it really is… it just takes a minute to get the hang of it.

You can see how coarse stage one is if you place it beside a stage three.

Changing your Rock Tumbler Barrel

Obviously if we just left our rock tumblers running to keep tumbling stage one grit, we would eventually erode the rocks away to nothing without ever arriving at a polish. We need to move onto stage two, stage three, stage four, and potentially more if you want that mirror shine.

Let’s start with getting that basic wet-look. 

To change your rock tumbler barrel:

1. Unscrew the lid. If you cannot remove the rubber seal, then break it with something flat but not sharp. I use the opposite end of a spoon.

2. Empty the dirty water into a container that you don’t mind destroying. Recycled plastic tubs are perfect. I currently use a large coffee whitener tin.

   1. A few tips on emptying – we don’t put it down the sink. This blocks your drains/pipes. We keep the rocks covered with the lid while we pour the water away or we end up sticking our hands in the slurry. We also rinse with water until it runs clear, then toss the slurry into the dirt in the back garden.

   2. Silica carbide grit occurs in nature but is usually man-made these days. Nevertheless, it is essentially muddy water. Don’t chuck it out the back if there are chemicals in it.

3. Once your rocks run clear, remove your rocks and clean out your barrel.

4. Replace the rocks, add in water to just cover them and no more (cold water, we don’t need pressure building up and shooting that lid off from steam), and this time add in a few drops of soap. Preferably a soap with no mineral content of its own (don’t want to scratch your newly tumbled rocks) but any soap will do. I have used a literal bar of soap before by cutting it up.

5. Set your rocks and soapy water mix to tumble for anything from two hours to a full day to whenever you remember them.

6. Repeat the drainage process, this time the soapy and dirty water goes down the industrial drain outside.

7. Rinse until clear, fill with water to just cover your rocks, and add a heaped tablespoon of STAGE TWO GRIT.

8. Repeat these instructions up until the final stage, with stage two, three, and four grits.

In most hobby rock tumbler sets your final stage will be stage 4. This stage will be either a very fine grit or a white polishing powder.

The Final Stage of Rock Tumbling

Add the white or fine powder/grit for your final polish cycle and run for a week as normal. You can use your ceramic beads at this stage if you have them. Using them earlier will wear them away. Empty it, rinse the rocks, add in a soap cycle, leave them overnight.

Empty your soap cycle and wash your rocks with warm to hot soapy water. When using a polishing powder, heat can be what seals the deal at the end. Your rocks are technically finished so leave them out on a cloth to dry.

If you have the Gemfoam from National Geographic, use this at the end with clean rocks and a clean barrel. Gemfoam pads are to be added to a dry barrel. We haven’t successfully used them yet as we put ours in with the polish and ruined them (so don’t do that!)

Where to Buy Replacement Rock Tumbler Grit

After you run out of the rock tumbling grits which come with your rock tumbler, you will need to replace these. You can go for the whole pack inclusive of rocks to polish as well with the National Geographic refill pack.

Otherwise, you will want at least four stages of tumbling grit to begin with. We suggest the following.

Buy Rock Tumbler Grits UK:

• F80 grit for stage one

• F220 grit for stage two

• F400/600/either/blend for stage three

• Stage four is often around 1200 grit for your final polish. Cerium oxide is a good alternative.

You can buy all four stages with ceramic beads and gemfoam from Nat Geo here, or get your four stages cheaper with no add-ons here.

Buy Rock Tumbler Grits US:

• F80 grit for stage one

• F220 grit for stage two

• F400-600 grit for stage three

• Stage four is usually around 1200 grit; cerium oxide is a good alternative.

You can also buy all four stages of National Geographic grits or these slightly cheaper versions we found.

In both cases (UK and US) you may continue polishing up into the thousands, but it is overkill for beginners.

Let’s Get Tumbling!

Other than that, the skill require to polish your own rocks without instructions all comes down to trial and error. At five years into our rock tumbler journey we are by no means experts, but if you do have specific questions feel free to ask us in the comments and we will do our best to get good answers for you.

Also, don’t forget to buy Scottish tumbled stones from the Stone Circle to help pay for articles like this one, which help other rockhounds learn their stuff.

All we want is to leave the world a better place than it was when we found it. Mineral specimens with a nice polish, included.

Black Basalt takes a lovely shine.