Perlage, also known as "circular graining" or "pearl pattern," is a decorative finishing technique used in watchmaking to enhance the aesthetic appeal of watch components, particularly those that are not immediately visible, such as the movement plates and bridges. This intricate pattern consists of small, overlapping circles that create a shimmering, pearl-like effect on the metal surface. The process of applying perlage involves using a rotating abrasive tool or brush to engrave the circular patterns onto the metal, often done by hand or with the aid of a machine for precision.

The primary purpose of perlage is to add a touch of elegance and craftsmanship to the watch's internal components, reflecting the watchmaker's attention to detail and dedication to quality. While it does not contribute to the functionality of the watch, perlage serves as a hallmark of high-end watchmaking, often found in luxury timepieces. This decorative technique not only enhances the visual appeal but also helps to protect the metal surfaces from oxidation and corrosion. Collectors and enthusiasts appreciate perlage for its artistry and the skill required to execute it, making it a valued feature in the world of horology.