Pearls Formation

Pearls are formed when the mollusk secretes thousands of very thin concentric layers of nacre, a secretion of calcium carbonate (aragonite and conchyolin) in a matrix that eventually coats an irritant, either man made or natural. The ideal pearl is perfectly round and smooth, but many other shapes, known as baroque pearl can occur. The finest quality of natural pearls have been highly valued as gemstones and objects of beauty for many centuries. Because of this, pearl has become a metaphor for something rare, fine, admirable and valuable.

The most valuable pearls occur spontaneously in the wild, but are extremely rare. These wild pearls are referred to as natural pearls. Cultured or farmed pearls from pearl oysters and freshwater mussels make up the majority of those currently sold. Imitation pearls are also widely sold in inexpensive jewelry, but the quality of their iridescence is usually very poor and is easily distinguished from that of genuine pearls. Pearls have been harvested and cultivated primarily for use in jewelry, but in the past were also used to adorn clothing. They have also been crushed and used in cosmetics, medicines and paint formulations.

Pearls Types & Sizes

Pearls can be natural, cultured, or imitation.

• Natural pearls are made by oysters and other mollusks.
• Cultured pearls also are grown by mollusks, but with human intervention: an irritant introduced into the shells causes a pearl to grow.
• Imitation pearls are man-made with glass, plastic, or organic materials.

Natural pearls are very rare, so most pearls used in jewelry are either cultured or imitation pearls. Cultured pearls usually are more expensive than imitation pearls. A cultured pearl’s value generally is based on its size, usually stated in millimeters, and the quality of its nacre coating, which gives it luster. Jewelers should tell you if the pearls are cultured or imitation.

Freshwater Pearls:

Freshwater pearls form in various species of freshwater mussels which live in lakes, rivers, ponds and other bodies of fresh water. Most freshwater cultured pearls sold today come from China.

In addition to the traditional white body color, these pearls come in a rainbow of natural colors as brilliant as lavender, tangerine, mauve, aqua-silver, peach and every shade in between. Their unique shapes range from very baroque to nearly round and are almost indistinguishable in their shape from Akoya pearls.

The varied shapes include potato-shaped and stick pearls, rice-shaped and button pearls, coin-shaped and drop pearls, off-round and round pearls. A perfectly round freshwater pearl is extremely rare. Their sizes range from 5mm to 10mm although they are often available in larger sizes up to 13mm.

Freshwater Pearls are most popular for their affordable price points.

                                                                                         (Courtesy of GIA.edu)

Tahitian South Sea Pearls:

Tahitian South Sea cultured pearls are native to the French Polynesian area. Exotic South Sea pearls from the Black-lipped oyster, Pinctada margaritifera, are more commonly known as Tahitian South Sea pearls. These pearls are often referred to as black but have a remarkable colour range that covers the spectrum from light, creamy white and grey, to regal greens, aubergines and deep blacks. These pearls have become some of the most sought-after, expensive pearls in the world. Due to their vast colour variations, matching these pearls for a single strand is an enormous task often requiring thousands of loose pearls.

Tahitian South Sea cultured pearls have an average size of 9mm to 14mm but some rare gems, larger than 20mm, have been found. Tahitian South Sea pearls are farmed in French Polynesia, the Cook Islands, the Micronesian Islands and, to some extent, in Japan, Thailand and The Philippines. 

Japanese Akoya Pearls:

Akoya pearls, produced by small Japanese oysters, are characteristically rounder than traditional Freshwater pearls. The Akoya oyster is the smallest commercially farmed, pearl-producing oyster. Due to this, the pearls do tend to be small. An average Akoya pearl is only 7mm while an average South Sea pearl is in the 12mm range. Akoya pearls are inherently round, although every harvest produces a percentage of baroque and keshi pearls. These pearls tend to have a bright lustre and shine, common to the Akoya but a shape and look reminiscent of a Freshwater pearl.

Most Akoyas are white to grey with pink, green or silver overtones. Akoya pearls are never naturally black. While the Akoya pearl is undoubtedly a more rare and valuable pearl than its Freshwater pearl cousin, it is only the third most valuable commercially produced pearl, falling behind White and Golden South Sea and Tahitian South Sea pearls. Japan was once the undisputed Akoya pearl producing centre of the world but has more recently lost that title to China where, in the last 5 years or so, pearls of equivalent quality have been produced in a much greater abundance.

The vast majority of the world's Akoya pearls, of 8mm or larger, are still produced in Japan.

White & Gold South Sea Pearls:

The finest White South Sea cultured pearls, Pinctada maxima, come from the waters of Australia and the Golden South Seas. The rarest of all are farmed mainly in The Philippines and Indonesia.

 South Sea pearls are generally much larger than other pearl types and have a unique lustre quality. These factors make South Seas both distinctive and valuable. All things being equal, South Sea pearls have a higher value and command higher prices than all other types of pearls. As with other saltwater mollusks, the Pinctada maxima is bead-nucleated. However, the growth period is approximately 3 to 6 years, unlike Akoya pearls which develop in less than half that time and sometimes in as little as 8 months. Being a delicate organism, this genus of oyster is particularly susceptible to disease and stress which is one reason why the culturing area for South Sea pearls is quite limited.

South Sea pearls can be found in the range of 8mm to 20mm with the average being 13mm. Although extremely rare, some have been found between 20mm and 30mm. Only 10% to 30% of each harvest will be round or near-round, so those strands are truly a rare commodity. Silver-lipped oysters generally produce pearls in the white, silver, aqua and blue family of overtones. Gold-lipped oysters develop the cream, champagne, vanilla and deeper golden varieties. Since the natural colours of South Sea pearls are so rich and beautiful, after harvesting, they are merely washed and buffed to remove any residue and to bring out their natural glow.

The majority of White South Sea pearls are cultured along the northwest coast of Australia. Although the majority of Pinctada maxima in Australia are collected in the wild and then introduced with hatchery-bred oysters to supplement the breeding program, in other areas the opposite is true. In both cases, wild oysters are mixed with the hatchery stock to keep the supply healthy and plentiful and all sources are closely monitored by government organizations to guarantee their wellbeing.

The larger size of South Sea pearls, the limited culturing area and extended growth period all combine to make the South Sea pearl the rarest of all pearl types. The lustre of South Sea pearls, whether white or golden, is deep and velvety, rich and luxurious. Only a small percentage of South Sea pearls are spherical and, as such, full strands of matched pearls are rare. Golden South Sea cultured pearl necklaces are considered by many to be the most rare and most valuable pearls in the world. Unlike any other type of pearl in the world, baroque South Sea cultured pearls have their own allure and exotic beauty. 

Pearls Care

Pearls are delicate and require proper care.

• Apply your makeup and perfume before you put on your pearls.
• Gently wipe pearls with a damp and soft cloth to remove sweat, perfume, body oil, or makeup if needed before returning your pearls to the jewelry box.
• Avoid situations which will scratch or damage the pearl's face.
• Avoid dehydration by storing your pearls in air-tight/moisture free environments. Don’t store pearls in an airtight package such as a plastic bag.  Pearls need moisture.
• Avoid subjecting pearls to excessive heat and/or strong sunlight.
• Avoid dipping pearl strands in water or wear them while bathing, as water can weaken the silk thread.
• Avoid exposing pearls to acids such as vinegar or cleaning agents containing ammonia or chlorine, bleaching agents or inks.
• Have your pearls restrung every one or two years, especially if you wear them consistently to prevent strand breakage. Silk thread is suggested, however, nylon thread is an acceptable alternative. The thread should be knotted between each pearl to prevent all the pearls in a strand from falling off should a break occur. Knotting also prevents possible damage from the pearls rubbing against each other. Ask your local jeweler to knot the strand in between beads to provide the strand with added protection. This way, if a string breaks, you only lose a single pearl.