South Sea Pearls

When you picture pearls, small, round white akoyas probably come to mind. These classic gems are popular and pretty, and are favored by everyone from young fashionistas to modern brides to society matrons, so they’re usually what we think of when we picture a traditional strand of pearls. But there are several types of pearls beyond the classic akoya. From Tahitian to freshwater, keshi to South Sea, each has its own unique characteristics and unquestionable beauty and is well-worth discovering.

If you’re looking for attention-grabbing jewelry—and have cash to burn—a South Sea pearl strand is a gorgeous, statement-making piece. The gems’ large size—they’re the largest pearls on the market—thick nacre and beautiful silver and golden colors are extremely luxurious, and naturally have a price tag to match. Let’s explore…

Background and History
As you may have guessed, South Sea pearls are named for the region in which they’re grown—a temperate, plankton-rich area situated between the southern coast of China and the northern coast of Australia. While the latter country produces most of the world’s South Sea cultured pearl crop—60 percent according to the Gemological Institute of America—Indonesia, the Philippines, Myanmar and Thailand also culture the gems.

South Sea pearls are extremely desirable today, so you might be surprised to learn that they’re relatively new to the market. In fact, it was the oyster’s shell, not its pearl-making ability, that Australians first coveted when they discovered P. maxima in the shallow waters of Australia in the 1800s. Demand for the shells grew quickly. According to GIA, within a few years of discovering P. maxima, Australia was supplying 75 percent of the world’s demand for mother-of-pearl.

Of course the oyster population couldn’t sustain this level of fishing indefinitely. By 1930, Australia’s wild oyster population was severely depleted, forcing the government to step in and set limits in order to protect the animals. The industry gradually declined and finally dried up during World War II, when fishing boats were called upon to help the war effort.

Two decades of relative quiet followed. That changed in 1950, when the Australian government decided to lift an earlier ban on pearl culturing, which it had feared would harm the natural pearl trade. Once the ban was lifted, pearl culturing began in earnest. According to GIA, farmers in Australia established the first commercial pearl farm there in 1956, and the industry gradually grew into the giant it is today.

Characteristics
If you get a chance to see a South Sea pearl up close, you’ll probably first notice its large size. At an average diameter of 13mm, South Sea pearls are about twice the size of the typical akoya. There are several reasons South Sea pearls grow so large. First, the oyster they’re grown in, P. maxima, is a relatively large animal, much larger than the oyster used to grow Japanese akoyas. In fact, P. maxima can grow to about 12 inches in diameter, which means it can accept a larger starter bead than a smaller oyster or mussel. Second, larger oysters are able to deposit nacre faster than smaller oysters, meaning they can grow larger pearls in a shorter amount of time. Third, the environment where the animals live is pristine, plankton is abundant and the water is warm. These all contribute to a healthy environment that’s perfect for marine health, nacre secretion and of course, pearl growing. (Because they filter so much water, P. maxima are particularly susceptible to changes in water conditions.) Finally, South Sea pearls typically have a two year growth period, compared to as little as eight months for some akoyas. Naturally, the longer the oyster is allowed to secrete nacre, the bigger the pearl will be.

Apart from their generous size, South Sea pearls are known for their satiny luster—a function of the way their nacre is deposited—and subtle array of colors, which most often include white, cream and silver. Indeed, P. maxima comes in only two varieties: silver-lipped or gold-lipped—names derived from the color of the outer edge of the shell’s interior, or mother-of-pearl, which helps determine pearl color.

Pearl Farming
To culture South Sea pearls, Australian pearl farmers breed oysters in hatcheries or, more commonly, collect the animals in the wild. (Conversely, their Indonesian and Philippine counterparts rely more heavily on hatchery-bred animals.) Because the oysters are solitary and often buried in sand, they’re difficult to find, so collecting wild oysters is a difficult task. And because the animals are delicate, care must be taken not to remove them from their natural environment for too long. In fact, early efforts at culturing P. maxima using techniques developed for the heartier akoya resulted in a 60 percent mortality rate, according to GIA. Later methods, developed specifically for P. maxima and the Australian environment, which keep the oysters in their natural environment as much as possible, have been much more successful.

In Australia, South Sea pearl oysters are nucleated when they’re about two years old and 4.7 to 6.7 inches in diameter. Working quickly to keep the stress of the animal to a minimum, highly skilled pearl nucleators surgically insert one nuclei into each oyster and return it to the water. (By contrast, freshwater mussels and akoyas can take several bead nuclei at once). P. maxima can be nucleated up to three times in its lifetime; the third and final time, when the animal is about six years old or so, produces the largest pearl, although this pearl usually has the thinnest nacre.

In Australia, oysters are collected from February to July, nucleated between March and December, and harvested in June, July and August, when water temperatures are coolest and the cultured pearls are at their most lustrous and colorful. During the pearl growing process, the oysters are stored at sea either on the sea floor in panels where divers tend to them, or, more commonly, on a long-line system, where net panels hold the oysters below the surface of the ocean hung from lines attached to buoys.

When farmers harvest South Sea pearls, they typically don’t treat them beyond washing them. The pearls are typically then shipped to be sold at major auctions; the prices that are set at those auctions influence prices around the world.

South Sea Jewelry
South Sea pearls are not as plentiful as Japanese akoyas, and experienced pearl sorters can go through as many as 10,000 pearls before they find even two to match for fine jewelry. As you can imagine, a strand of large, round, high quality South Sea cultured pearls is very expensive, costing upward of tens of thousands of dollars. Because these strands are outside the means of most people, jewelry designers make South Sea pearls more affordable by using baroque or drop shapes, which are just as beautiful, yet less costly. If you ever get the opportunity to purchase a piece of South Sea jewelry—whether a costly strand or a single baroque pendant—I highly recommend it! You can pick up one for me while you’re at it. J