Circled pearl

circled pearl
A pearl with raised rings around its surface, caused by the pearl's rotation during its development in the mollusk ...

Button pearls are flat on one side and round on the other and circled pearls have a ring. Baroque pearls are irregular in shape. The luster depends upon the reflection of light from the surface of the pearl.

See also: Tahitian pearl, Size, Baroque, Diameter, Pinctada