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What you should know about Pearls


What is a pearl, what are its characteristics?

A cultured pearl is a pearl formed by an oyster, composed of concentric layers of a crystalline substance called nacre deposited around an irritant purposely placed in the oyster’s body. Nacre is a pearly substance secreted by the oyster or the mollusc and is a pearl-like form of calcium carbonate. Natural pearls are formed by deposits of nacre around an irritant which accidentally lodges within the body of an oyster. An Imitation is anything else which resembles a pearl but has a surface created by a manufacturing process - this is an imitation or simulated pearl and must be labelled as such. The value of a pearl comes from the unique ability of the crystalline nacre to absorb, refract and reflect light, imparting a distinctive quality, termed orient, to natural and cultured pearls. Orient is the deep inner glow and shimmering iridescent characteristics of sea-grown pearls. The deeper the lustre and iridescence, the more precious the pearl. Size contributes to the price of a pearl. As it is more difficult for oysters to grow large pearls, they are more scarce. But two pearls of different sizes may be valued the same if the smaller pearl is superior in orient. Shape determines value too. The more symmetrical the shape, the more valuable the pearl. Examples of symmetrical pearls include round, pear, tear shape and oval. Pearls of irregular and symmetrical shape are termed baroque. Oysters grow pearls in many different shapes, from perfect spheres to long flat angel wing pearls. Surface perfection contributes to value. The surface of a perfect pearl appears satiny smooth, but when viewed closely, natural or cultured pearls may appear to have irregular surfaces which do not detract from value, as do disfiguring blemished. You don't need a magnifier to detect blemishes - when they are present, they are easily seen. Rarity increases the value of any jewel. Cultured pearls themselves are relatively rare, as they can only be developed in limited areas of the world's oceans and take years to grow. A perfect pair of pearls is very rare because nature makes few pearls exactly alike in orient, shape and colour.

Types of pearls

Akoya -One of the most familiar type of cultured pearls, they are grown in pearl oysters off the coast of Japan. Akoya pearls are know for their lovely orient and warm colour. They rarely grow more than 9mm in size.

Mabe - Large hemispherical cultured pearls grown against the inside shells of oysters instead of within the body. Less expensive than regular round cultured peals and, because of their hemispherical shape, they are usually mounted in such jewellery as earings, rings and brooches.

Fresh water - Pearls cultivated in mussels, not oysters, found in fresh water lakes and rivers. Fresh water pearls generally are elongated in shape and have a milky translucent appearance. Their wide range of interesting shapes and colours make up in fashion appeal for their relatively low value. In china, shape and lustre are rapidly improving and round freshwater pearls are readily available.

Keshi - Seedless pearls which form naturally in many cultured pearl oysters in both Akoya and South Sea pearls. They also come in a variety of colours, shapes and sizes.

South Sea Pearls

Australian - Large cultured pearls (10mm and larger) grown in large oysters (called Pinctada Maxima) in warm waters off the Australian coast. These pearls are found in a variety of colours including white, silver, gold and rose. Australian South Sea pearls are generally rare and valuable.

Indonesian - Large cultured pearls (8mm and larger) generally smaller in size and creamier in colour than their Australian counterparts.

Tahitian - Large cultured pearls (10mm and larger) which are grown in large oysters (Pinctada Margaritifera - black lipped) off the islands of French Polynesia. Colours range from soft gray to black, with hues or overtones of reds, blues and greens.

When choosing cultured pearls
Look for lustre and orient in the shadow area of the pearl, not in the area upon which the light is shining. Colour tones should be clear, not dull or muddy. Watch out for cracks, chips or disfiguring blemishes. In addition, all pearls in a strand should blend well, particularly in regard to lustre, orient and colour. Roll a strand of pearls along a flat surface to determine if all pearls are strung through their exact centres; all of them should roll evenly without an eccentric wobble. Buy the best pearls you can afford, then choose the clasp. A decorative jewelled clasp can always be purchased later.

Selecting necklaces
Choose a cultured pearl necklace for its effect on your appearance and personality. Long necklaces are informal and versatile, while short necklaces can be demure or sophisticated. Choker necklets enhance a long neck and longer strands slenderise and appear to elongate the neck. For fair skinned women, rose-hued pearls are most flattering, while cream and gold colour pearls set off darker skin tones best.

Here is a guide to necklace lengths and terminology:
Choker - 35-4Ocm (14"- 16") in length. Should nestle around the base of the neck in single or multiple strands.

Princess - 45cm (18") in length. Halfway between a choker and matinee length.

Matinee - 50-60cm (20"- 24") in length. Should fall to the top of the cleavage.

Opera - 70-80cm (28"-32") in length. Should fall to the breastbone.

Sautoir or Rope - Any pearl necklace longer than opera length.

Bib - Multiple strands of pearls, each shorter than the one below, nested together in one necklace.

Graduated - A necklace comprised of pearls which taper downward in size from large pearls in the centre to smaller pearls at the ends.

Uniform - A necklace which appears to be comprised entirely of pearls of the same size, though there is generally a slight difference in size between the centre and the end pearls for a more proportionate look.

Pearls come in all shapes
Cultured pearls come in a variety of shapes and the following are the most common: Round - The pearl is perfectly symmetrical. Semi-Round - The pearl is slightly off round. Egg - The pearl is an oval shape. Button - The pearl is a cushion shape. Semi-Baroque - The pearl's shape is irregular. Circled - This is a ringed pearl. Heavy Baroque - The pearl is irregular in shape with tails. Mabe - The pearl is a half sphere with one flat surface and comes in a variety of shapes including oval, round, pear and heart etc.

Cultured pearl care

  • Cultured pearls are precious jewels and should be treated as such. The following guidelines may assist you in caring for them.
  • Don't toss them carelessly into a purse or jewel box where they may be scratched by hard metal edges or harder stones.
  • Don't wear pearls while bathing, in the shower or while playing sport.
  • Put your pearls on after applying cosmetics, hairsprays and perfume.
  • Before any cleaning is undertaken, seek the advice of your JWNZ jeweller.
  • Have your pearls re-strung once a year if worn frequently.
  • Have a knot between each pearl which will prevent loss if the string breaks.

Why you should buy pearls from a JWNZ jeweller
Admiring and reading about pearls may make you feel knowledgeable, but you're still not an expert. It you're thinking about buying pearls you need a trained professional jeweller whom you can trust, so you can be advised on quality as well as a suitable style.

Your JWNZ jeweller can recommend a necklace, for example, that will best enhance your appearance and provide advice about the care and protection of your pearls. Also, a suitable clasp can further enhance your strand of pearls. You can be assured of professional service and specialist, honest advice from your JWNZ jeweller.