The oysters are nucleated with a bead composed of mother-of-pearl and a small piece of mantle tissue. This bead becomes the nucleus of the pearl and is the reason akoya pearls are more often perfectly round.
Carbon definition, Chemistry. a widely distributed element that forms organic compounds in combination with hydrogen, oxygen, etc., and that occurs in a pure state as diamond and graphite, and in an impure state as charcoal.
Carbon dioxide (chemical formula CO2) is a colorless and odorless gas vital to life on Earth. This naturally occurring chemical compound is composed of a carbon atom covalently double bonded to two oxygen atoms.