Pearl 101
The nature of the pearl
Known by many romantic names, from "jewels of the sea" to "tears of God", pearls have been treasured for thousands of years.
A pearl is, technically, a nacreous, organic gem formed in the body of a mollusk. It is nacreous because it is made from layers of nacre or Mother-of-Pearl, a nacre made of aragonite crystals composed of calcium and other organic matter that lines the inside of the mollusk. These layers are deposited around a nucleus, which is often a foreign object that is trapped—or in the case of cultured pearls, inserted—in the mollusk's soft tissue, eventually forming a pearl. It is organic because it is the product of living processes and a living environment, and continues to require constant warmth and contact even after it has been set as jewelry, to keep its surface glow. Pearls are formed in certain species of bivalves or clams—in the case of South Sea pearls, from the noble Pinctada maxima.
