1.Cyst pearls-refer to the whole pearls that are cultured from within the shell fish inside an oyster or mussel.
2. Mabe pearls – are the blister or half pearls grown on the inside of an oyster shell. (Both Japanese and South Sea oysters can produce mabe). They are formed by cutting out the mabe then the mother of pearl is removed, the inside bead taken out and replaced with a resin with a backing of mother of pearl glued back on. Various shapes and sizes are available.
3. Keshi pearls – are accidental pearls, formed when a piece of the mantle tissue breaks away from the main sac to form a solid pearl of irregular shape at the same time the first pearl is being formed.
4. Imitation pearls – pearl beads manufactured by man to imitate the pearl. Can be made of glass or plastic coated beads.