Pearl is the birthstone for the month of June and it is generally accepted as the wedding anniversary gemstone for the 3rd and 30th years or marriage. The pearl has been a symbol of sacred power and the goddess of love for hundreds of years. In the ancient Mediterranean world, shells and pearls were often symbols for the great goddesses. As the pearl is born from the oyster so was Aphrodite born from a marine conch.
According to dLoewi.com Pearls are an organic gem, called organic because they are created by living creatures. Each pearl begins its existence as a piece of grit or other particle that makes its way into the shell of a marine or freshwater mollusk, some types of oysters and clams. A defense mechanism kicks-in and coats the particle with layer after layer of a substance called nacre, or mother-of-pearl1, which eventually becomes thick enough to form a pearl.
Natural pearls are formed when an accidental intruder enters a mollusk's shell and continuous layers of nacre grow like onion skins around the particle. Natural pearls vary in shape depending on the shape of the piece being coated.
Natural pearls have always been considered rare and are quite expensive. They are usually sold by carat weight. Most natural pearls on today's market are vintage pearls.
Like natural pearls, cultured pearls grow inside of a mollusk, but with human intervention. A shell is carefully opened and an object is inserted. Shapes of objects vary, depending on the final shape of pearl that's desired.
Over time the object becomes coated with layers of nacre. The depth of the nacre coating depends on the type of mollusk involved, the water it lives in, and how long the intruder is left in place before being harvested. As nacre thickness increases, so does the quality and durability of the cultured pearl.
Cultured pearls are sold by their size in millimeters.
Saltwater pearls originate within a saltwater mollusk. Saltwater pearls can be either natural or cultured.
Freshwater pearls grow inside of a freshwater mollusk — one that lives in a river or a lake.
Beauty is in the eye of the beholder, and this is certainly true when it comes to Pearl shapes. Pearls are natural organic substances, they can occur in a wide variety of shapes, many of which are quite unique and interesting. The round pearls you most commonly seen and are by no means the only shape in which pearls are found!
Perfectly round pearls are actually quite rare. The eventual shape of the pearl is determined by a number of highly variable factors which occur inside the oyster as the pearl is developing. The pearl often assumes the same shape as its nucleus (the irritant which was placed inside the oyster to initiate the formation of the pearl). If the nucleus is not perfectly round, the resulting pearl is likely to reflect this irregularity. The pearl's positioning within the oyster also plays a role in determining its shape. For example If the pearl develops against the shell, it will become more flattened on that side.
There are three broad categories that pearl experts divide Pearls into, based on their characteristics:
Spherical pearls: These pearls are round, which is traditionally the most desirable shape. They are the "classic" pearl shape that is most familiar. The rounder the pearl, the more expensive its price tag.
Symmetrical pearls: This type include pear shaped pearls and other shapes that have symmetry from one side to another, but are not round.
Baroque pearls: Barouque pearls are irregularly shaped pearls. They are often the least expensive category of pearls, but are unique and quite beautiful.
Within the three broad shape categories, pearls can be classified into seven basic shapes:
Round: Round pearls are perfectly spherical -- the shape most people think of when they think of a pearl. Because of their relative rarity and "classic" nature, they are highly desirable. Round pearls fall into the spherical category.
Near-Round: These pearls are not perfectly round. Instead, they are slightly flattened or elongated, rather than being a perfect sphere. Nonetheless, they are so nearly perfect that they, too, are classified as spherical.
Oval: These pearls are shaped like an oval -- narrower at the ends than they are in the center. Ovals are categorized as a symmetrical shape.
Button: Button pearls are flattened to some degree, making them resemble a button or perhaps a disk rather than a perfect sphere. These pearls are often used in earrings, where the flattened side can be attached to the setting. Buttons are also categorized as symmetrical.
Drop: Drop pearls are pear or teardrop shaped. The drop can either be "long" or "short," depending on its proportions. These pearls make attractive earrings or pendants. This is also a symmetrical shape.
Semi-baroque: These pearls are slightly irregular in their shape. For example, a pearl which might otherwise be considered an oval, button, or drop pearl, but which is not symmetrical in nature, would be considered semi-baroque. Semi-baroque pearls fall into the baroque category of shapes.
Baroque: This is a pearl which is both non-symmetrical and irregular in shape. The baroque pearl can be purely abstract in its shape, or it can resemble a cross, stick, or some other shape.
Within these basic categories and definitions, there can be many variations. Some pearls, for example, develop with one or more grooves or rings encircling them. These pearls are known as ringed or circled. This adjective can be attached to the primary shape in order to more fully describe the pearl, such as "circled round" or "ringed oval."
The shape of the pearl is one of several factors which determine its quality and value. Round and near-round pearls are the most valuable, because of their rarity. Symmetrical shapes are generally considered to be more desirable than baroque shapes. Baroques, however, can be extremely unique, thus increasing their desirability more than might be expected based on their shape alone.