A cabochon is a convex cut for gemstones, often used on opaque or softer gems. It is also one of the most basic cuts, and most jewelers and lapidarists are familiar with the form, since it is an excellent starting lesson. Although the cut is simple, it can totally transform the look of a piece of rock, bringing out the magic of unique shapes and lines in the rock. Cabochons are used in ornamental jewelry, just like regular gems, and they are available in a number of shapes and sizes to suit all needs.
The upper surface of a cabochon cut is gently curved, while the back is flat, allowing for easy working and setting. No facets are cut into a cabochon, but the stone is highly polished once it has been cut. Opaque stones are well suited to cabochon cuts, as are stones which are very soft, since the curve and high polish will help to hide scratches. Brittle stones may also be polished into cabochons, since they could break during the faceting process.
The shape of a cabochon may vary. Ovals, rounds, and teardrops are common and popular shapes. Some jewelers cut their cabochons in irregular shapes which are designed to showcase certain features of the individual rocks. The cut may also vary in size from quite small, for use in earrings and rings, to very large, in the form of a centerpiece on a necklace or brooch. A rock which has been cut into a cabochon may be described as en cabochon, or it may just be called a cabochon.
The cut is not suited to all gemstones. Diamonds and other highly translucent stones, for example, tend to look dull and plain when they are cut into cabochons, since there are no facets to reflect light, creating a sparkle. Other stones look excellent in a cabochon cut, such as those with banding or eyes. The cut will highlight these natural features, rather than hiding them behind facets, and the stone will really stand out as a result.
To cut cabochons, jewelers cut a rough form from the rock and then use a saw to trim it to shape. The shaped stone is mounted on a dop stick so that it can be curved and polished. The part of the stone which is attached to the stick will become the flat back of the finished stone. Once the stone has been shaped and polished to satisfaction, the jeweler removes it from the dop stick and gently breaks away the hard wax used to attach the stone.