How are Pearls Made
Pearls hold a prized position in the many Eastern and Oriental cultures for over thousands of years. Long before the west discovered these precious dewdrops, it adorned the Eastern nobility. Not only were they cherished for their beauty and smoothness, it was held in awe, inspiring many legends and beliefs that spoke about how they were formed. According to the old Arabian legend dewdrops filled with moonlight fell into the ocean, they were swallowed by oysters, who formed the pearls. Ancient Chinese believed that pearls were conceived in the brains of dragons, whereas a Polynesian myth says the Oro, the Polynesian god of peace and fertility, came down to earth on a rainbow and offered a special pearl oyster to man. The Arabs believed pearls represent perfection and completeness, while the Chinese regard the natural black pearl as a symbol of wisdom.
Pearls have fascinated mankind since time immemorial, simply because of the way it is formed and history associated with it. It is believed that it was Christopher Columbus who introduced pearls to the American soil, who on his third trip back brought bags of pearls bartered along the coast of Venezuela. Queen Elizabeth 1(1533-1603) too had quite a passion for pearl strings. The royalties got their pearls from pearl beds like Gulf of Manaar, Indian Ocean, Persian Gulf, the Red Sea, etc.
How are Natural Pearls Made?
Before the concept of cultured pearls, all pearls were formed naturally, without the intervention of humans. Any shelled mollusk can produce a pearl by natural processes, but they are all not valued as gemstones. Pearls formed in the family of nacreous pearl bivalves, become the pearl oysters who live in the sea, while the river mussels, a different group of bivalves live in freshwater, several species of marine pearl oysters in the family Pteriidae, etc are the pearls that have value and are the actual 'pearls'.
Natural pearls are formed when a microscopic irritant or parasite enters a bivalve mollusk accidentally and settles inside the shell. To protect itself the mollusk secretes nacre (calcium carbonate and conchiolin) covering the irritant with it. This secretion is repeated continuously, and the irritant keeps getting covered in layers thus producing a pearl. Hence not all natural pearls are round, but at times take on an irregular shape depending upon the irritant. An irritant could be anything such as a grain of sand, organic debris, animal tissue, parasites, etc. For a pearl to be formed naturally it takes many years, decades in certain instances, making them rare and very expensive. Over a thousand oysters have to be searched for just one pearl of value.
How are Cultured Pearls Made in Oysters?
As pearls were expensive it was concentrated with only a few, however, the beginning of 19th century saw wealth being diversified, and interest in pearls growing. This is when the concept of pearl farming or cultured pearls set in. We owe cultured pearls to Japanese researchers Mise and Nishikawa who discovered a specific technique for inducing the creation of a round pearl within an oyster. However, it was Kokichi Mikimoto who beat them in acquiring a patent for this technique. And thus began the rush for cultured pearls; cream, black and pink.
Cultured pearls require human assistance. To form a cultured pearl a piece of oyster epithelial membrane with a nucleus of shell or metal, or a pre-formed bead is inserted into the oyster. The oyster then secretes layers of nacre covering the outside surface of the implant. A cultured pearl is formed within a year's time. Cultured pearls from the Oriental countries are very popular in use for creating pearl jewelry.
The value of a pearl depends upon it being natural or cultured, and yet again on its size, shape, quality of surface, orient and luster. Natural and cultured pearls can be distinguished using gem testing techniques, natural pearls will show a series of concentric growth rings, whereas a cultured pearl will show a solid center with no concentric growth rings. Another method to check (if the jeweler allows) is to gently rub the pearl against the edge of a tooth, if they feel slightly rough, they are natural or cultured, else you have in your hands a really good imitation.
How does one describe a pearl, to me it is simple aesthetic perfection, and therein lies its mystery. These are made by so simple an organism and yet able to excite the mind of a human being by such a great measure. Pearls are nature at its best, unlike all other gems they don't need cutting, polishing, or working around their imperfections, they are just there to pick and appreciate, in their natural state.
