Both shell valves are fan shaped with an 'ear' on either side of the apex of the valve. The right valve is strongly convex and tends to be off-white, yellowish, or light brown in colour, often with bands or spots of darker pigment. The left valve is flat and is light pink to reddish brown in colour. Pecten maximus grows up to 15 cm long and both valves each have 15-17 radiating ribs.Also known as the King scallop, Giant scallop, escallop and Coquille St. Jacques.