The art of polishing rocks is also called Lapidary. It is considered a fun-filled hobby that teaches you the benefit of patients. Polishing rocks can lead to impressive results, and you can share them with your family and friends.
Polishing rocks is an easy task even when done by hand and does not require any expensive equipment. You can also buy a rock tumbler that does the same job much faster than by hand, and you can also polish multiple rocks in one sitting.
The result of polishing a rock leads to a beautifully finished stone with a smooth surface and the inner beauty of the stone out for people to see. You can use these rocks as a decoration piece and send them to your friends and family as gifts.
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Which Rocks can be Polished?
When it comes to polished rocks, a lot of them do not yield any good results. They are too brittle and break easily, or the final product is not worth all the trouble. If you are looking for rocks to polish, then keep in mind that rocks that are made from microcrystalline Quartz are very good for polishing.
Before polishing a stone, they need to be properly smoothed in a tumbler, and a lot of rocks break in this process. But rocks with microcrystalline Quartz are much stronger than other rocks; they also yield much more interesting colors and textures and have different patterns inside.
The most common types of rocks that can be tumbled and then polished include the following.
- Petrified Wood
The above-mentioned rocks are most commonly used for polishing and are the most widely available rocks. They are tough, durable, and very hard when polished; these rocks reveal a beautiful surface, textures, and pattern.
Pro-Tip for Rock Polishers:
As we said earlier, rock polishing is the last step and the finished product of rock tumbling. For surviving the tumbling process, rock needs to be strong free from any fractures, cavities, and voids.
When selecting rocks for your polishing, make sure that they do not have the following.
Where can you get Rocks for Polishing?
There are people who are lucky enough to live in an area where there is an ample supply of good rocks for polishing. The most common places for collecting these rocks are along the river banks, on beaches, or you can find them scattered around the surface.
As people’s interest grows in this fun little hobby, many vendors sell different types of rocks suitable for polishing. You can easily get even some of the rarest rocks for polishing from stores.
Below we have mentioned the list of rocks that produce great results after polishing.
Different types of Quartz:
How to Polish a Rock:
When it comes to polishing rocks, there are two different methods, each with different advantages and disadvantages. Below we have mentioned the two methods and how you can polish rocks using these methods.
Polishing a Rock With Hand:
For polishing a rock by hand, you will need sandpapers with different grades. The process starts from a rough (high) grade all the way to smooth (fine) grade sandpaper. Polishing a rock with your hand is divided into the following steps.
1. How to select a Rock:
When it comes to polishing a rock, you can choose which rock you like. When it comes to polishing by hand, many factors come into consideration that makes rock polishing a lot easier.
An easier stone to polish makes your job easy, and stones like onyx, calcite, and limestone should be a great start. Harder stones take more time and energy to polish by hand; however, hard rocks yield better results. They are a lot smoother and have better color patterns.
(For checking a rock’s hardness, scratch the surface of the rock. If the scratch looks chalky, then the stone is soft)
2. Cleaning the Rock:
The next step is to clean the rock thoroughly. Make sure that the rock does not have any sand or dirt by washing it with soap. You can also use a scrub brush if you feel it is necessary.
After you have washed the rock, dry it with a cloth.
You can choose a rounded rock during the selection for easier sanding, or you can use a small hammer and a chisel to chip off the edges. Make sure to use safety glasses during the chipping to avoid any accidents. You can also use gloves to protect your hands as well.
Once the stone is in the desired shape, take it to the next step. If you do not have a chisel, bash the rock against a hard surface to break off any unwanted piece.
The sanding process can be divided into three steps: rough grade, fine grade, and removing any scratches.
For rough grade, 50-grade sandpaper, which is the roughest sandpaper, is used. After breaking the rock into the desired shape, this sandpaper is used to shape the rock further. It also helps in removing any bumps or cavities.
With 50 grade sandpaper, you should give the rock an even surface so that the next process is easier and even as well.
The next step is to use finer-grade sandpaper. The most common sandpaper used for this process is 150-grade sandpaper. If the 50-grade sandpaper left scratches, then they can be removed with the help of 150-grade sandpaper.
Make sure that you cover the whole surface area of the stone to give it an even surface.
The last step is by no means mandatory if you are happy with the results from the 150 grade, then leave it as is. If you see any scratches even after 150 grade, then use 300 to 600-grade sandpaper. The fine grade from 300 to 600 sandpaper will only smooth the surface and will not leave any new scratches.
Polishing the Finished Product:
The last step is to polish the rock. Take a piece of leather and a bit of polish, preferable tube polish. You can easily purchase these items from any hardware store if you don’t already have these things in your house.
Use a small amount of polish to coast the rock and rub it with the leather piece. You can also apply another coat of polish if needed.
Polishing a Rock with Tumbler:
Polishing a rock with a rock tumbler is very easy, and the result is a lot better than hand-polished rocks. The shape is more defined and has a shine to them. The rock tumbler has another aspect that is better than hand polish is that they can polish multiple stones at a time.
With a rock tumbler, you also need to do less. Just put them on a tumbler and wait for it to be completed. The finished product also has a more natural surface and a cleaner look. Polishing with a rock tumbler is broken into the following steps.
1. Rock selection:
Before you go tumbling any rocks in a tumbler, make sure that they are of similar hardness and shape. If you use rocks with different hardness, the harder rock will scratch and wear down the softer rock.
Also, make sure that you do not place rocks with different shapes. Rounder rocks get polished faster than irregular rocks.
2. Cleaning and Weighing the Rocks:
First, wash the rocks for excess dirt. Now place the rocks in the tumbler and fill it either ½ or ⅗. Now take them out and weigh the rocks so that it is easier to know how much grit you will need.
3. Using a Coarse Grit:
After weighing the rocks, put them back into the rock tumbler and measure out .1 lbs of grit for every pound of rocks used. After that, fill the barrel to the top with water and seal it shut. Now run the rock tumbler for a day and check up on progress after 24 hours.
Tumble these rocks for 3 to 7 days, check every 24 hours, and make sure nothing goes wrong. The coarse grit will smooth out the outer surface and remove any deformities like bumps.
It should take about three days for round rocks, and for irregular rocks, it should take about seven days of spinning to get a smooth surface.
4. Using a Medium Grit:
The next step is to use a medium grit. After using the coarse grit for 3 to 7 days, remove the rocks and put them on the pan. Clean the grit from the rocks by washing them with water and not washing the grit in the sink. The grit from the stones will clog your pipes and block them; instead, throw the grit in the garbage.
Now place them back into the rock tumbler and put the same amount (.1 pound for 1 pound of rock) of medium grit into the rock tumbler. Fill the rock tumbler with water, spit it for 3 to 7 days, and check every 24 hours.
After 3 to 7 days, stop the tumbler and place the rocks in a container to clean them for the next step.
5. Using a Fine-Grit:
Place the cleaned rocks back in the tumbler once again and use .1 pounds of fine grit for every pound of rocks used. Fill the rock tumbler with water, put a lid on and start the tumbling process. This cycle should take around seven days to complete, but check progress every 24 hourfs.
The fine grit can also be considered as polishing the rock. It removes all the scratches and makes the surface smooth and shiny.
After seven days, stop the rock tumbler and take the rocks out. Clean them with water and make sure to remove all the grit from all the crevasses. Clean the barrel thoroughly as well to avoid any future performance issues.
Sometimes rooks do not get a smooth and shiny finish after the tumbling process. To give these rocks a proper finish, use leather and tube polish to polish the surface. Make sure to cover all the surfaces of the rocks so that you will get an even shine.
Frequently Asked Questions:
Which rocks will polish best?
The rocks that can be best polished are hard and dense. Also, the rocks with round shapes are polished evenly and more easily.
How to shine landscaping river rock?
After some time in the sun, the landscaping river rocks lose their shine. To restore their shine, you can use a sealer on them. Before applying a sealer, make sure that the rocks are clean; otherwise, you will also lock the dirt in with the stone.
How to apply a high gloss sealer?
Before applying a sealer, make sure that the outer surface of the stone is as clean as possible. Clean the stones with soap and water to make sure that no particles of dust remain on the surface.
You can apply a high gloss sealer to landscape river rocks by using a pump-action spray. However, it is recommended to use a roller or a paintbrush for some products.
Rock polishing is a simple and easy task; it serves as a fun little hobby for people of any age. If you can not invest in a rock tumbler, don’t worry; you can easily polish rocks with your hands using sandpapers.
We highly recommend you try out this hobby. The results are impressive.