Cabochon cutting, also known as cabbing, is one of the most popular forms of gem cutting. So, what exactly is cabochon? In short, it is a gem that is cut in convex form and highly polished, with a rounded top and no facets and a flat, slightly domed base.

Not only are cabochon one of the most popular forms of gem shapes, but they are also the most traditional, meaning that they have been around for centuries. Why are they so popular? Many gems are cut in the cabochon form because they have specific properties that are displayed only in this form, such as:

  • Asterism, otherwise known as the star effect
  • Chatoyancy, otherwise known as the cat’s eye effect
  • Iridescence, such as the opal

A cabochon also exemplifies two of the properties that many people treasure in colored gems. One of these properties is that cabochons are pure color. The second is that cabochons are about as close to the natural material as you will find in a gemstone because they have only been shaped and polished, but otherwise unaltered.

Cabochon Cutting Tools

When it comes to cutting your own cabochons, it is sometimes better left to the professionals, as it can be tedious work. But with lots of practice and plenty of patience, anyone can learn how to shape and create their own cabs.

There are a wide variety of machines and tools that help with cabochon cutting, and depending on your skillset, you may want something more advanced or more fundamental. Below are only a few of the tools used when cutting cabochon.

1. Rock Rascal

A rock rascal is one of the least expensive cabochon cutting tools and is one of the smaller machines that are used. It only holds a one-inch wide wheel, and users will have to change out accessories regularly.

2. Genie by Diamond Pacific

The Genie by Diamond Pacific is currently one of the most popular cabochon cutting machines on the market and comes with six permanently mounted wheels. The first two are 100 and 260 grit diamond on solid wheels while the other four range from 280 to 12,000 grit, and all wheels have a foam backing that conforms to the curvature of the stones.

Cabochon Carving Tools

With Cabochon cutting, also comes cabochon carving. This provides a whole new dimension to your gemstone and helps you create unique, beautiful pieces. That being said, below are a few options for different tools used for cabochon carving.

1. Flex Shaft

A flex shaft is great for cleaning, polishing, sanding and more, and many come with varying speeds and a set of bits for these purposes. Flex shaft units are generally great tools for jobs that require intricate detail and precision. 

2. Carving Tips

Carving tip kits come in all shapes and sizes with a variety of different bits. Carving bits can be made of a variety of different materials including plastic, wood, ceramic and metal, though most bits are generally diamond impregnated steel.

Cabochon Cutting and Carving Techniques

Once you’ve got your tools and gemstones, you are ready to get to work. When it comes to cabochon cutting and carving techniques, it may seem complicated, but the reality is that the oval is the most common shape, and there are only a handful of carving techniques to alter your cab further.

Cabochon Cutting

When it comes to cutting your cabochon, there are a few steps you’ll want to follow. While the oval is the most common shape, other shapes are manageable and only require a few adjustments.

  • Slabbing – Slabbing is the initial cutting of the cabochon. Some people chose to use a template while others are better off just eye-balling the piece as they go.
  • Shaping – Once the slab is cut, you’ll begin shaping the material. You’ll start by grinding down excess material until you’ve reached your desired shape.
  • Smoothing – After you’ve achieved the desired shape, you will begin to sand out the coarse scratches on the gem’s surface. This is a time-consuming step as you will more than likely need to use a combination of grit sanders to achieve the desired look
  • Polishing – Polishing is the final step to getting your gem done. And while there are some different polishing methods, they will all help you get a mirror polish on any material.

Cabochon Carving

There are a few basic carving styles when it comes to cabochon carving, and we’ve listed them below.

  • Cameo – Cutting the material away from the design, leaving the design above the surface of the gem.
  • Intaglio – Etching the design into the surface of the material.
  • Reverse Intaglio – Etching the design on the back of a transparent gem, creating the effect that the design is floating within the stone.

Cabochons are a Classic

Cabochons have been around for centuries and remain one of the most popular cuts around, and with a little time and practice, stone cutters can perfect both cabochon cutting and carving and soon create their own beautiful gemstones.