Large pearls that come from the Pinctada Maxima oyster are known as South Sea cultured pearls. These pearls range from 9mm to 20mm in size and come in a wide variety of colours including silver, golden, pink, green and blue. Most of these large, creamy pearls come from Australia where government regulations permit harvesting only a few months each year. The Philippines, Indonesia and Thailand have also produced a limited number of South Sea pearl oysters.