How Cultured Pearls Are Grown

Bred for Quality
Early pearl cultivation involved planting a nucleus in wild oysters. While some seek to jump-start the natural process by implanting a tiny piece of pearl mantle inside the oyster, others use beads designed to create a larger pearl in the shortest period of time and help to control its shape. Along the way, Japanese scientists identified strains of oysters with the best pearl-bearing qualities and focused on using them to produce pearls of high luster and clear, uniform color.

Implant the Nucleus
Technicians open the live pearl oysters gently, then surgically implant a small shell bead, along with a tiny piece of mantle tissue. This bead is the nucleus around which the oyster secretes layer after layer of nacre, the substance that forms the pearl. This step of the culturing process requires tremendous skill and precision. The oysters will only allow their shells to be pried open less than a centimeter wide, or they will reject the nucleus. Experienced technicians use exacting tools to make the tiny incisions.

Back to the Sea
The nucleated oysters are quickly returned to the sea, housed in individual mesh pockets that are suspended from floating rafts. The oysters feed and grow in sheltered bays rich in natural nutrients. As time passes, the oysters secrete lustrous layers of nacre around the implanted bead. In winter, the oysters are moved to warmer waters. Pearl technicians monitor water temperatures and feeding conditions daily at various water depths, and move the oysters to take advantage of the best growing conditions.

Pampered Oysters
Periodically, the pearl-bearing oysters are lifted from the sea for cleaning and health care. Seaweed, barnacles and other growths are removed from their shells, and they are treated with compounds to prevent parasites from injuring the tender flesh of the oysters. These precious oysters are meticulously protected from every conceivable threat to ensure the finest resulting pearls. However, typhoons, red tides of plankton and predators all take their toll before the pearls are ready to be harvested.

The Birth of a Pearl
Once the oysters are brought back to shore, the pearl farmers take inventory of the long-anticipated harvest. Of the millions of oysters nucleated every year, only a tiny fraction of them produce high grade pearls. On average, about half of the nucleated oysters do not even survive to bear pearls. Less than five percent of the survivors yield pearls with the ideal shape, luster, and color to be considered fine quality. The few pearls that make the cut are then cleaned, soaked, and sorted.

Natural Beauty
The newest crop of pearls is treated to series of gentle treatments to prepare them for their jewelry debut. The pearls are first soaked for several days in a mild cleaning solution under intense flourescent light, to remove any deposits and odors they may have accumulated during their days in the ocean. The pearls are then bathed in a wooden vat of finely crushed walnut shells. The natural oils from the shells provide a soft, gentle polish without harming the integrity of the pearl's surface.

The Perfect Match
After they receive their luscious spa treatments, the pearls are painstakingly matched. To assemble a single strand, workers must comb through thousands of pearls to find ones that match for size, shape, color, luster, and surface quality. First, the pearls are poured into special sieves that separate them into size groups. They are then sorted into increasingly smaller batches according to shape, then bodycolor, overtone, and finally, quality. This time-intensive, detailed work may take months to complete.

A Place of Honor
The pearls are finally ready to be drilled and mounted. But before a pearl earns the honor of being set into a piece of fine jewelry, it undergoes more rigorous screening processes. The matched lots are further separated into perfect pairs to create a pair of earrings, for example, or a well-matched group will be carefully arranged to make a subtly graduated strand. One by one, each pearl is individually drilled and strung onto temporary 18-inch strands called loose hanks.