South Sea pearls are found in a variety of different shapes, which can be used in a diverse range of jewellery designs to suit differing tastes. Circle pearls develop with one or more groves or rings encircling them. The circles are formed due to constant pressure placed against the pearl as it is developing within the oyster. The circles can be sparing with just a few noticeable on the surface, or the pearl can be completely covered. Circle pearls can be used for a range of different jewellery creations.