The Journey of a Pearl
The birth of a pearl is a miraculous event! Live oysters below the surface of the sea grow pearls. Gemstones must be cut and polished to bring out their beauty, but pearls need no such treatment to reveal their loveliness. They are born from oysters complete with a shimmering iridescence, lustre and soft inner glow unlike any other gem on Earth.
A natural pearl begins its life as a foreign object, such as a parasite or piece of shell that accidentally lodges itself in an oyster’s soft inner body where it cannot be expelled. To ease this irritant, the oyster’s body takes defensive action. The oyster begins to secrete a smooth, hard crystalline substance around the irritant in order to protect itself.
This substance is called “nacre.” As long as the irritant remains within its body, the oyster will continue to secrete nacre around it, layer upon layer. Over time, the irritant will be completely encased by the silky crystalline coatings. And the result, ultimately, is the lovely and lustrous gem called a pearl.
Cultured pearls share the same properties as natural pearls, and most pearls cultured today are cultured. The only difference is a person carefully implants the irritant in the oyster, rather than leaving it to chance. We then step aside and let nature create its miracle.
In a process referred to as nucleation, highly skilled technicians carefully open live pearl oysters, and with surgical precision make an incision in the oyster’s body. Then, they place a tiny piece of “mantle tissue” from another oyster into a relatively safe location. Then, they place a small round shell or nucleus, beside the inserted mantle tissue.
The cells from the mantle tissue develop around the nucleus forming a sack, which closes and starts to secrete nacre. The nucleated oysters are then returned to the sea where, in sheltered bays rich in nutrients, they feed and grow, depositing layer after layer of lustrous nacre around the nuclei implanted within them.
The oysters are given the utmost care during this time while suspended in the water. From the rafts above, technicians check water temperatures and feeding conditions daily at various depths, moving the oysters up or down as appropriate. Periodically, the oysters are lifted from the sea for cleaning and health treatments. Seaweed, barnacles and other seaborne organisms that might interfere with their feeding are removed from the oysters’ shells. The shells are also treated with medicinal compounds to discourage parasites.
Over time, after eight to 36 months of growth and care, the oysters are ready for harvest. Those that have survived the many perils of the sea are brought ashore and opened. All pearls must be cleaned and washed to remove residue and odors. They are typically tumbled in rotating barrels with salt during this procedure. The tumbling must be closely monitored; otherwise some of the nacre may wear off.
When everything has gone well, a beauty is revealed — the result is a lovely, lustrous and very valuable cultured pearl. Chinese freshwater pearls and Akoya pearls are often treated with chemicals after drilling. This whitens them and makes the color look more even.
Sorting, Matching & Stringing
After harvesting, gem quality pearls must be sorted. Because no two pearls are ever exactly alike, sorting pearls is an extremely difficult and time-consuming effort performed by experts. Each pearl must be sorted by size, shape, color and lustre, so it is handled hundreds of times. After sorting, the pearls are drilled with great care and precision.
Finally, it’s time for matching and stringing. This can be even more difficult than sorting, because now experts must compare pearls that are similar in size, shape, lustre and color — looking for nearly exact matches. As an example, to find 47 pearls for a perfectly matched 16-inch necklace, a pearl processor must cull through more than 10,000 pearls.
Quality of Pearls
Millions of oysters are nucleated every year, but only a small proportion live to produce fine-quality cultured pearls. On average, only 50 percent of nucleated oysters survive to bear pearls, and of them, only 20 percent bear pearls that are marketable. The rest are simply too imperfect, too flawed to be called jewels. A perfect pearl is truly a rare event; less than five percent of nucleated oysters yield pearls of such perfect shape, lustre and color as to be considered fine gem quality