Cabochon

The cabochon (often shortened to 'cab') is the oldest gem cutting style, predating faceting by millennia. It is the preferred cut for opaque or translucent stones like turquoise, malachite, and moonstone, and is required to display chatoyancy and asterism. Cabochons are described by their outline shape (oval, round, cushion, teardrop) and their dome profile (low, medium, high). A high dome amplifies optical effects in cat's-eye and star stones. Transparent gems are rarely cut as cabochons in modern trade, though sugarloaf cabochon sapphires are a notable exception.