Baroque pearls are pearls with an irregular non-spherical shape. Shapes can range from minor aberrations to distinctly ovoid, curved, pinch, or lumpy shapes. Most cultured freshwater pearls are baroque because freshwater pearls are mantle-tissue nucleated instead of bead nucleated. Cultured saltwater pearls can also be baroque, but tend to be more teardrop-shaped due to the use of a spherical nucleation bead. 

The most valuable of baroque pearls are the South Sea and Tahitian pearls. These pearls are produced by Pinctada margaritifera (black-lipped oysters) and Pinctada maxima (gold-lipped and white-lipped oysters). Although these are a variety of cultured saltwater pearls, the amount of time that the pearls are cultured dramatically increases the depth of the nacre, and the likelihood of producing a baroque pearl. 

Most Tahitian pearl farm harvests, for example, produce more than 40 percent baroque and semi-baroque pearls. Western Australia is currently the world's largest cultivator of Pinctada maxima gold-lipped oysters. Tahiti is the number one cultivator of Pinctada maxima black-lipped oysters.