A natural pearl is a product of an oyster or mollusk that an irritant has accidentally found it’s way into the mollusk tissue, with no human intervention. The irritant (intruder, parasite), entered naturally, causing the irritation, causing the mollusk to produce the conchiolin and nacre that will produce a Pearl.
In a cultured Pearl, man implants an irritant, a mother of pearl bead that is called the nucleus. The process by which the cultured pearl is produced is similar to that of the natural pearl. The mollusk produces the conchiolin and the nacre, coating the irritant, the intruder, coating it layer after layer and producing the finished pearl. The oyster or mollusk controls the pearl product it will produce, humans wash the mollusks periodically, control their food, maintain constant water temperature and control pollutants.
It takes several years to raise a mollusk and produce a fine pearl, the more thicker the nacre of a pearl, the more years it takes to produce the pearl.
The Cultured Pearl
By Nicholas Paspaley
To understand today’s cultured pearls, one must delve a little into the origin of the natural pearls of yesteryear. The key to understanding natural pearls is to know the differences in the “mother shell” or the “host oyster” which produces the pearl. Not all pearls are born equal, hence the wide variation in appearance and value of both natural and cultured pearls.
The world’s oceans contain many oysters, most of which can grow a pearl of some form. Most relatively abundant oysters have no commercial value in a pearling sense because they produce nether mother-of-pearl (the material that makes the knife handles and buttons) nor pearls of significant value. Pearls produced by these oysters were referred as in natural pearl days as “seed pearls.” They were quite common, inexpensive and were used mostly in embroidery and semi-precious jewelry.
Mother of pearl shells are one of nature’s true mysteries. In the depths of the ocean the shells, horny and brown on the outside, are lined inside with thick layers of mother- of -pearl nacre and iridescent beauty. Most intriguingly, they isolate any intruder by secreting it with concentric layers of nacre to produce a pearl, one of the most magnificent objects known to man!
These mother-of-pearl oysters are members of the “Pinctada” family and are responsible for almost all the world’s great natural pearls. Only two are truly valuable for their nacre. The rarest, largest (average size 10 inches) and most valuable is the giant Silver and Gold lipped “Pinctada Maxima” from the South Seas - the waters of Northern Australia, Indonesia, and the Philippines, Thailand and West Burma. The other is the smaller (average size 6 inches) and more abundant Black lip Pinctada Margaritifera from Tahiti and other tropical oceans.