Pearls are formed in shellfish - especially oysters and mussels. Pearls vary in colour from white, white with a hint of colour, to brown or black. They are sensitive to acids, dryness and humidity, and so are less durable then many other gems. Natural pearls have been harvested from the Persian Gulf, the Gulf of Manaar ( Indian Ocean) and the Red Sea for thousands of years. the coasts of Polynesia and Australia produce mainly cultured pearls. Both freshwater and saltwater pearls are cultivated in Japan and China. Freshwater pearls occur in the rivers of Scotland, Ireland, France, Austria, Germany and Mississippi (USA). Pearls are associated with Pisces and were once thought to be the tears of the gods and angels. Pearls harmonizes bodily rhythms with those of the natural cycles of the moon and the seasons, this enables hormonal cycles and biorhythms to find their natural level. They also eases mental overload, soothing and healing any negative struggle in one's life. Pearls surround negative energy with light and are a powerful force for prosperity.