cabochon

A cabochon is a gemstone cut that features a smooth, rounded, convex top and a flat or slightly curved bottom, with no facets. The design emphasizes the stone’s color, pattern, or optical phenomena rather than brilliance. Cabochons are especially common for opaque or translucent stones and for those that display chatoyancy (cat’s eye) or asterism (star effects).

Common materials cut as cabochons include agate, jasper, chalcedony, jasperoid, turquoise, jade, obsidian, coral, and opal. Opal, moonstone, and similar stones are often shown well in cabochon form because the domed surface can enhance play of color or milky luster. Cabochons are also used for pebbly or banded patterns where facets would interrupt the natural design.

Cutting and finishing involve shaping the rough stone into a desired form and then grinding a dome on the top with progressively finer abrasives, followed by polishing. The bottom side is kept flat or slightly curved to allow the stone to sit securely in metal settings. Shapes vary widely, including round, oval, cushion, button, teardrop, and freeform silhouettes.

Etymology traces the term to the French caboche, meaning “head” or “rounded lump,” reflecting the stone’s domed appearance. Cabochons remain popular in jewelry for statement pieces and for stones whose beauty is best shown without facets. Synthetic and glass imitations are also produced in cabochon form to mimic natural materials.