These oyster pearls are natural pearls from the rainbow-lipped oyster.Oysters are saltwater bivalve filter feeders and they create natural pearls in all the colors of the rainbow; lavender, pink, red, blue, green, purple, silver, gold, black and brown with varying shades and combinations.It is not unusual to get 3 or 4 color variations on one pearl.These are natural pearls that are found within the organism and they are mostly symmetrical with rounds, buttons, drops, and ovals. Some are baroque and very interesting. Most of the pearls are in sizes from seed to 30 carat pearls.