Records of commercial pearl harvesting go back 2500+ years, making pearls one of our most ancient and treasured gems. They are also uniquely feminine gems. Attempts have been made at marketing pearls to men, with little success. Pearls have always been and still are associated with women, and with ladies in particular.

There is almost endless variety when it comes to pearls. Pearls are available in almost unlimited choices for colour, shape, size, quality, and style. This is a little general guide to help you work out at least some of the differences.

Cultured Pearls

Cultured pearls, whether done in saltwater or freshwater, are created by oysters and sometimes other mollusks (including abalone, clams, and mussels), but these are shellfish  that have had some help from humans. In brief, the shellfish has an irritant inserted in the shell, and it coats the irritant (the "seed") with secretions (known as "nacre")  that become pearls.

Naturally occurring pearls that are not cultured (i.e., that occur naturally and without interference from human beings) are extremely rare and very highly prized, as only one in several million shellfish ever produce a pearl spontaneously.

Freshwater Pearls

Freshwater cultured pearls are farmed in fresh water and grown in pearl-producing freshwater mollusks.. The irritants used in making freshwater pearls are smaller than saltwater pearls, and freshwater pearls have generally more solid pearl material (nacre). Freshwater pearl cultivating technique usually produce twenty or more pearls in one oyster.

Freshwater pearls have a special appeal since they come in a wide range of colours with much more variety than saltwater pearls. This is achieved by adding very small quantities of different metals to the water on the pearl farm. The colours of freshwater pearls can be very different, and many of these colors are not found in saltwater pearls.

Freshwater pearls can be found in almost any shape that you can imagine: round, drop, rice, button, oval, semi-round, circle or ringed, baroque and semi-baroque. Because of its popularity, the round shape is usually the most expensive, but as always, personal preference dictates the shape each customer will find most beautiful.

Saltwater Pearls

Saltwater cultured pearls are farmed in salt water and most commonly grown in oysters. Only one pearl is grown per oyster, so this makes saltwater pearls more expensive than freshwater pearls. Countries known as producers of saltwater pearl are Japan, Burma, Indonesia, Thailand, Philippines, Australia, and Tahiti (Tahitian pearls are the most expensive and considered the finest in the world).

Other saltwater mollusks such as clams and abalone are also sometimes used to produce pearls, as well, including "blister" pearls, which are created by attaching a bead or other seed to the shell of the mollusk (frequently an abalone) and then cutting it off the shell after it has become coated with nacre. Mabe pearls are assembled from blister pearls.

Saltwater pearls do come in a variety of colours and shapes, but they're not as varied as those available in freshwater pearls.

In the world of saltwater pearls, South Sea pearls some of the finest in the world, with prices to match (hundreds or thousands of dollars, depending on the pearls and the jewellery item).

Shell Pearls

A good alternative to cultured pearls are the manufactured pearls known as shell pearls. These are made from the pulverised shells of the South Sea oyster, or may be made from the shells and mother-of-pearl of other pearl-producing mollusks, and are sometimes known as "reconstructed" shell pearls. Good quality shell pearls are nearly flawless, tend to be big, they're perfectly shaped, and they usually have a beautiful lustre, either high-gloss or more satiny.

High quality shell pearls can be difficult to tell from the real thing. Not long ago, a Japanese marketing firm reported that South Sea shell pearls were inserted into a lot of South Sea pearls as a marketing experiment and buyers could not tell the difference.

The biggest difference (other than price!) is the lack of a gritty texture. Shell pearls are smoother than pearls. This is because they are created in a lab so the environment is cleaner than a lake or ocean.

Pearl Shapes

Just as pearls come in a variety of colours, they also come in a variety of shapes, including round, semi-round or near-round, button, drop or pear, oval, baroque, semi-baroque, and ringed or circle. Pearls also may go by names such as "rice pearls" (because they're shaped something like pieces of rice), "seed pearls" (because they're very small), "potato pearls" (because they're shaped like potatoes), and a few others. The names given to the shapes of pearls are varied and often imaginative.

Perfectly round pearls are the rarest and most expensive, and are generally used in necklaces, or strings of pearls. Semi-round   are also used in necklaces or in pieces where the shape of the pearl can be disguised to look like it is a perfectly round pearl, such as rings or brooches.

Pear-shaped or drop pearls are used as pendants and are highly prized as earrings.

Button pearls are like a slightly flattened round pearl and can also make a necklace, but are more often used in single pendants or earrings where the back half of the pearl is covered, making it look like a larger, round pearl.

Other pearl shapes are used in various ways, some of them quite ingenious and beautiful, and depend on the shape and size of the pearl.

Baroque pearls are simply irregularly shaped pearls. Freshwater pearls are most commonly baroque due to the nature and shape of the freshwater molluscs that produce them.

Other Pearls of Wisdom

Akoya pearls are cultured saltwater pearls. The term "Akoya" refers to the original Japanese techniques used to farm them in oysters, but the term is now used more widely. Akoya pearls are still produced in Japan, but also in China and the South Seas.

Perfectly round, smooth pearls are very rare and very expensive. Most pearls have some degree of natural irregularity on their surface or in their shape. Many people feel that these irregularities and organic qualities enhance the beauty of the gems.

The term "lustre" (or "luster") refers to the translucent, reflective quality of the surface of the pearl.

Pearls absorb oils and other chemicals from the skin. While the oils can be beneficial to the pearls, improve the lustre, and keep the pearls from drying out, chemicals (including perfume) can permanently damage pearls. (For more information see our Guide on Jewellery Care).