What Is Rock Polishing Called?

Casey Grove Penn State

October 12, 2022

The first step in rock polishing is cleaning. First, you must remove all rough grit from the stone. Once the stone has been cleaned, you can burnish it with soapy water. This will coat the stone with a layer of clear resin. Repeat this step several times to achieve the desired shine.

Next, you must sand the stone. Start with medium-grade sandpaper, then gradually use finer-grain sandpaper until you have the desired shape and smoothness. Once the shape and smoothness of the stone are achieved, you can use a commercial rock polish or mineral oil.


A stone polisher may also use another technique to finish rock pieces. Known as burnishing, this technique adds a particular shine to rocks. It uses silicon carbide, a rock-hardening compound with nine hardness on the Mohs scale. The particles are different in size and can be used to shape the stone. The earlier stages of the burnishing process use coarser particles, while the later stages use finer ones.

During the process of rock burnishing, rocks must be cleaned of any dust or debris. Too much grit can make rocks unusable. It is, therefore, essential to follow these steps carefully.

Rock Polishing

Tumbling is a technique for polishing rocks. Unlike other rock polishing methods, this process uses progressively finer grit to achieve the desired smoothness. First, rocks are roughed up using rough grit and then washed; then finer grit is added to polish them further. Finally, excellent grit is added to polish the very last edges of the rock. The rocks are put into a jar containing a polishing agent, usually cerium oxide, during tumbling. The rocks are also surrounded by cushioning agents such as plastic pellets during this process.

Tumbling can be done with a wide variety of rocks, including gemstones. While the most common types of rocks are moss agate, rose quartz, and green adventurist, other rocks can also be tumbled. The results will depend on the hardness of the stones and their size.

Preparing rocks for tumbling

Before you begin tumbling rocks, you should thoroughly inspect them. You should look for flaws and cracks and discard any rocks that do not meet your standards. Also, all rocks must be of similar hardness, as rocks with differing hardnesses will destroy each other. During this step, you should also break rocks with visible fractures, which can cause damage to other rocks in the barrel.

Next, you should check the grain and pit of your stone materials. Stones with a coarse grain and those with considerable pitting will not polish well. This is because the pitted rocks will block all the other stones from polishing, and grit from the previous stages will escape the pits and ruin the batch.

Using a rock tumbler

A rock tumbler is a vital tool to help you polish your rocks. These devices have two primary components: a barrel and a motor that rotates to grind and polish the rocks. The barrel contains rocks and minerals to be polished. The motor provides continuous movement, smoothing out rough edges and bringing out the beautiful colors of the stone. Tumbled stones are used for various purposes around the world. They also provide a better light reflection than polished stones with hard edges.

Before starting the process, you must clean the tumbler barrel thoroughly. Ensure the tumbler is free of grit and rock fragments from previous tumbles. Also, make sure the tumbler barrel lid is clean.