The difference between a natural pearl and a cultured pearl used in pearl jewelry may come as a shock to many. For an oyster/mollusk to produce a pearl, an irritant must become lodged inside. The oyster then has a defense mechanism against this “intruder” where it produces a substance called nacre. This nacre covers the irritant and, over time, the layers of the nacre create a pearl.
In a cultured pearl, such as an Akoya pearl, the irritant is not obtained by any natural means. It is placed in the oyster by man. Other than that, everything is the same. The pearl still grows inside the oyster the exact same way, and a pearl is produced that is just a beautiful as any round natural pearl. The only difference is a helping hand lent by humans. Even the huge South Sea pearls and elegant Tahitian pearls are produced in this way, with farmers tending the oysters in the ocean, in hopes of producing beautiful, gleaming gems.