Category: EDUCATION

Mabé cultured pearls grow in saltwater mussels and some oysters, forming on the inside of the shell, rather than in the mussel’s tissue. Also called blister pearls, their size is determined by the size of the implant.

CULTURING MABÉ
Either a half-round plastic bead or piece of mantle tissue is glued on the inside lip of the host shell. As the mussel secretes pearl nacre it forms a domed blister. At the end of the growth period, the pearl is removed from the shell, the nucleus removed, the
blister filled with epoxy and then backed with mother of pearl before setting.

MAKE THE GRADE
As with other cultured pearls, assessment criteria include luster, surface, and strength of color. The most desirable color is white with pink undertones, but an increasing interest in dark, smoky, and blue colors has emerged.

DELICACY AND CARE
Handle Mabé cultured pearls with care. Their thin nacreous layer can crack or damaged by misuse.

WOULD YOU LIKE THAT LOOSE OR FINISHED?
Mabé comes both ways. Choose rings, earrings, or pendants from our Mabé jewelry or select loose Mabé cultured pearls and a mounting in one of our many metal qualities.

Although originally produced in Japan, 90% of the world’s freshwater pearls now come from China. Unlike other pearls on the market, freshwater pearls typically do not come from an oyster at all. Most are farmed in varieties of freshwater mussels,
particularly Hyriopsis cuminigii. Freshwater pearls are generally irregular in shape but new farming and pearl-enhancement technology produce more round pearls in a new array of colors in sizes up to 9.5mm. Freshwater pearl harvests are typically bought while in the shell. Because they are plentiful, they are the most
affordable pearls and are widely used in jewelry.

CORNMEAL AND WAX?
In their natural state, freshwater pearls are not marketable for jewelry and require enhancements. After cleaning and sorting, they are pretreated in a warm and cold chemical solution. Unless they have a strong color, they are bleached. At this point some are dyed to provide the dazzling rainbow colors that inspire fashion jewelry. Finally all receive that finishing touch: they are polished with a mixture of cornmeal and wax. Now they’re ready to make their way in the world.

THE SMALL, PROLIFIC TRIANGLE SHELL
Though only 5cm to 6cm long, each triangular-shaped Hyriopsis cuminigii receives 12 to 16 grafts of mantle tissue rather than a round nucleus. The tissue is placed directly into a mussel’s mantle to initiate nacre production and the shell produces an
amazing up to 40 pearls. These pearls range in size from 4.0mm to 10.0mm, but larger ones are less likely.

When you think of a simple pearl necklace for a bride or to accent that little black dress, the Akoya pearl sets the standard as the premier choice. Best-known of the cultured pearls, their roundness, nacre depth, and consistent luster have positioned
them as the preferred choice for a timeless statement of good taste.

PINCTADA FUCATA MARTENSII
The P. fucata or Akoya oyster is the smallest pearl producing oyster in the world, yet each produces four or five 2.0mm to 9.0mm pearls. Water temperature and mineral content influence pearl quality and production with cool to cold water producing the
best results. Akoya producing mollusks are found in ocean waters bordering many areas worldwide, but for years most P. fucata were found off Japan’s shores with Japan dominating Akoya production. In 2010, China surpassed Japan in pearl production. Most Chinese Akoya pearls are processed in Japan.

WHO DEVELOPED CULTURED PEARLS?
Mikimoto is the name most frequently associated with Akoya cultured pearls, but he did not invent the process. That honor goes to British biologist William Saville-Kent, living and working in Australia. He taught the technique to Tokichi Nishikawa and
Tatsuhei Mise who brought it to Japan. In 1916, Nishikawa was granted a patent, and he married Mikimoto’s daughter. Mikimoto helped refine modern-day pearl culturing techniques and production. Successful culturing emerges from thoughtful
planning, patient tending, and nurturing of the producing mollusks. It requires an enormous investment of time, money, science, and people.

Often called black pearls, Tahitian pearls grow in the warm, turquoise lagoons of French Polynesia and other islands in the South Seas. Their opalescent black hue shimmers with peacock green, gray, and purple overtones for a sensual, smoldering
statement in jewelry designs for both men and women.

THE SCOOP ON COLOR AND SIZE
Tahitian pearl colors range from gray to black with pure black extremely rare and very valuable. Consistent color tone makes pearls highly desirable with peacock tones demanding the highest prices. Tahitian pearls are harvested between 8.0 mm to 15.0 mm. Sizes up to 20.0 mm occur rarely and are highly prized.

P. margaritifera, or black-lipped oyster, is a large tropical oyster that can live up to 30 years. In the 19th century, free-diving

PINCTADA MARGARITIFERA
Polynesians braved sharks and the physiological challenges of deep water diving to harvest it. Only one in 15,000 P. margaritifera produced a natural pearl, but the European button industry had an insatiable appetite for the inner shell that all but
devastated this oyster population.

TRULY TAHITIAN
Today, a complex cultivation process has resurrected French Polynesia’s pearl industry with P. margaritifera farmed in numerous atoll lagoons. They are also farmed in the Marshall, Cook, and Solomon Islands and the waters off Northern Australia. In all locations, strict government regulations assure pearl quality
and preservation of the species.

GET THE LOOK
What shows off a Tahitian pearl best? It depends on the recipient. Single pearls set in cuff links or as a tie stud make great gifts for men who seek a sophisticated look with natural appeal. For women of all ages, the choices are many. Few gems offer greater
drama than strands of Tahitian pearls — dynamic for day or evening wear. Used individually or in combination with white or golden pearls, black pearls create superbly fashionable jewelry that, with proper care, will last for generations.

The legendary allure of South Sea pearls comes from their transparent luster and unique play of colors, or “orient,” that imparts a luminescent beauty. These qualities define the finest nacre and make South Sea Pearls the most valuable of all pearls. The finest of these pearls have nacre measuring between 3.0mm and 6.0mm.

Colors
Color overtones range from white pink and silver pink to dark gold. Australian pearls can throw fancy colors including red gold — extremely rare and highly regarded. Stuller’s South Sea cultured pearl strands arrive at your store with a guarantee of natural luster and color — no enhancements. This is the South Sea pearl quality you want.

How Extraordinary is a Matched Strand?
The meticulous matching required to create an extraordinary strand can take up to a decade. This process leaves no room for compromise.

AUSTRALIA
Australian oysters and ocean conditions are generally credited with producing the largest and finest quality pearls. From the 1800s, it was the primary source of the world’s largest and most valuable pearls. Aware that their pearls would be in high demand, Australia pioneered the South Sea cultured pearl industry, coaxing the sensitive Pinctada Maxima oyster to yield pearls —no easy feat.

LIFESTYLE OF THE FAMOUS PINCTADA MAXIMA
P. Maxima is the largest pearl oyster, and it is rare, unable to survive outside small remote areas of natural habitat. Culturing it is extremely difficult. Labor-intensive farms must be situated in the isolated locations that meet P. Maxima’s highly specific needs. Each oyster can grow only one pearl at a time and takes about two years. It can only be reseeded three to four times. Not every P. Maxima will produce a pearl. Most South Sea cultured pearls range from 10.0 to 15.0 mm taking two years to grow. Larger pearls up to 20mm take four to six years of growth. Australia protects its wild oyster stocks by strictly enforcing production quotas.

MORE ABOUT P. MAXIMA
This amazing oyster lives up to 40 years and can grow to 300mm in shell length. Impressed? Wait. Like many other saltwater oysters, it functions as both a male and a female during its life. It matures first as a male at 110mm to 120mm or three to four years. By 170mm half are females and by 190mm all are females.

WHERE ELSE ARE THEY CULTURED
Originally exclusive to Australia, South Sea pearls are cultured in Indonesia, Burma, and the Philippines, but the characteristics and quality of these pearls can vary greatly. Indonesia and Burma produce mainly white to yellow and also gold, while the Philippines produce mainly yellow and gold.

Traditional Genuine Birthstones:

Daily Care
As an organic gem, pearls are vulnerable to chemicals found in cosmetics, hair spray, and perfume. To preserve the luster of your pearls, always put on your jewelry after applying make-up and styling products.

Pearls can also be harmed by perspiration. Before placing your pearls back in the jewelry box, wipe them gently with a soft cloth.

Storage

Contact with other jewelry may scratch pearls. Avoid tangles by fastening clasps, then lay each jewelry piece in a separate compartment of your jewelry box. When traveling, use a protective jewelry pouch or wrap each item in a soft cloth. Pearls can dehydrate when stored too long, so enjoy them frequently.

Cleaning
Never use an ultrasonic cleaner on your pearls. It can damage their nacre. Occasionally wipe your pearls gently with a cloth dipped in mild, soapy water. Then rinse the cloth in fresh water and wipe the pearls clean. Dry them with a soft cloth.
If pearls come into contact with an acid substance such as fruit juice, vinegar, or other chemicals, immediately wipe clean with a soft cloth. Be careful not to submerge your pearls in water as this will weaken the silk thread.

Maintenance
From time to time, check the clasps or screws holding your jewelry together. With frequent wear, even well cared for pearls may loosen and they will require restringing.

Selecting Pearls
Pearls are classified by origin and then graded by size, shape, nacre thickness, color, luster, and surface clarity. These qualities are not considered to be of equal importance when arriving at the final grade. When selecting pearls, be familiar with the Five Virtues of pearls to assist you in selecting your ideal pearl. However, the most important thing to remember when selecting a pearl is that “beauty is in the eye of the beholder.”

Luster
For cultured pearl experts, luster is the single most important indicator in evaluating pearl quality. Luster is what separates the superior from the inferior and the extraordinary from the ordinary. Throughout history, this unique attribute has separated pearls from all other gems. Luster describes the beauty you see as light travels through the nacre of the pearl. Luster derives from the pearl’s countless layers of pearl nacre, the natural pearly substance that forms the body of the pearl itself. It is the nacre of the pearl that causes light to refract from the depths of the nacreous layers through minute prisms, giving each pearl its unique lustrous appearance. Stuller only supplies pearls of excellent luster, due to the quality and thickness of the nacre. Importantly, the luster of these pearls is natural and untreated, and their beauty will not diminish over time if cared for properly.

Complexion
Pearls may have surface characteristics, which may or may not detract from the pearl’s beauty depending on the quality, depth, or visibility of the blemishes. Pearl nacre is a beautiful matrix of calcium carbonate crystal laid on tile-like formation by the oyster. The appearance of the nacre is determined by several factors including whether the calcium crystals are flat or prismatic, the perfection with which the tiles are laid, and the fineness and number of tiles. When the tiles are laid in a perfectly uniform pattern the nacre will appear identical over the entire pearl surface, thus creating the flawless pearl.

Nature is not normally flawless and some tiles may be imperfectly laid. This results in surface blemishes and imperfections beneath the nacre’s surface. The effect on the pearl’s beauty depends on the degree of visibility of these imperfections. This is described as the pearl’s complexion.

Surface complexion quality refers specifically to the abundance or absence of physical blemishes or marks. When evaluating complexion (the trade uses terms such as blemish, spotting, and cleanliness), remember that cultured pearls are grown by live oysters in a natural environment. As such, there are many uncontrollable forces that affect the surface.

Size
Cultured pearls are measured by their diameter in millimeters. They can be smaller than one millimeter in the case of tiny seed pearls or as large as twenty millimeters for a mature South Sea pearl. The larger the pearl, other factors being equal, the more valuable it will be.

Shape
Classic shapes range in descending order of value from round to near-round, and from oval to drop. More contemporary shapes include circlé and baroque. Popularity of certain shapes or the rarity of others can result in a premium price for particular shapes. It’s important to understand that in pearl industry terms, the shapes from round to drop are pretty symmetrical, while anything baroque denotes a pearl that is completely asymmetrical or freeform. These unusual shapes usually occur in Japanese cultured pearls as well as Tahitian, S outh Sea, and freshwater pearls.
The photographs of the shapes shown are representative samples of the various shapes and qualities available. As a product of nature, each pearl is rare and unique. The pearls you purchase may not look exactly like the images shown.

Color
Cultured pearls come in a variety of colors from rosé to black. The desirability of different pearl colors is a matter of individual taste. The most popular color is white or white with slight overtones. Pearls that are naturally colored, rather than color enhanced by artificial means, will add value to the pearl. Most South Sea cultured pearls offered by Stuller have natural color and luster and are not enhanced.

AGTA Codes:

Caring for your Gemstone from AGTA

Gems are among the most durable of nature’s creations. With a little care, they will be as beautiful for generations to come as they are
today. Keep in mind these gem care tips.

The best way to clean your gemstone jewelry is in a bowl of water with a few drops of ordinary dish detergent. Using an old toothbrush or other soft brush, scrub
gently behind the stone where dust and soap can collect. Then just rinse and pat dry with a soft cloth.

A home ultrasonic cleaner should be used with extreme caution. It can be used to clean Ruby, Sapphire, Diamond, Amethyst, Citrine, Garnet, Chrysoberyl, and
unadorned gold jewelry, but it may damage gems like Coral, Emerald, Lapis Lazuli, Pearls, Peridot, Tanzanite, Tourmaline, Turquoise, and any gem that has
many inclusions. When in doubt, don’t use it.

Remove your jewelry before vigorous activities.

Everyday household items can ruin your gemstone jewelry. Make sure you don’t expose your gems to the chemicals in cleaning products, hair care products,
fragrances and cosmetics.

When getting dressed, put your jewelry on last. At the end of the day, take your jewelry off first. Store your jewelry in a cloth-lined box or pouch and keep them
away from other jewelry, which might scratch them.