Natural pearls, Japanese Akoya, Chinese Freshwater, or Tahitian South Sea - with so many pearls, who can keep them all straight? As the beautiful birthstone for the month of June, pearls can be found in a variety of hues that will flatter anyone’s skin tone. So, what should you know when buying or wearing pearls?
How are pearls formed?
Natural pearls are formed when a foreign body finds its way into a mollusk and the mollusk protects itself by secreting a substance called nacre to cover the irritant. As this is a random occurrence in nature, natural pearls are very rare and therefore, very expensive. Virtually all pearls are cultured, which means they are grown in mollusks with some human intervention. Akoya and South Sea pearls are cultured in saltwater by implanting a bead nucleus to start the pearl formation, while freshwater pearls are cultured by implanting a small piece of mollusk tissue instead of a bead. In either case, the size and variety of the mollusk determines the possible size and color of the pearl.
No matter what the origin of the pearl, there are specific quality factors which are taken into account in determining the pearl’s value, and ultimately its beauty. These factors include size, shape, color, luster, surface, and in the case of a pearl strand, how well they are matched.
What is the best size pearl to buy?
Cultured pearls range in size from as small as 1mm to as large as 20mm. The most popular size is around 7-8mm. Slightly smaller sizes might be preferred for younger girls or petite women, while taller or more full figured women may want their pearls a little larger. With all other factors being equal, the larger the pearl, the greater its value. Pearls larger than 10mm are generally black Tahitian, white South Sea or large freshwater.
When it comes to shape, round and near round pearls are most valuable due to their rarity, but beautiful pearls can also be found in off-round or free form shapes referred to as baroque or semi-baroque.
What colors do pearls come in?
The palette of pearl colors includes white, cream, golden, pink, gray, black and virtually everything in between. In addition to the basic body color, many pearls have color overtones (such as rosé or silver) which affect their appearance. The most valuable colors in the light body group are pink, pink rosé and white rosé, with the latter being the most popular. But, the “best” colors are largely a matter of personal taste depending on a person’s skin tone and the color of clothes they enjoy wearing.
What is the most important pearl quality?
It is generally agreed that luster is the single most important factor affecting the beauty and value of a pearl. Luster refers to the brilliance and reflectivity of the pearl’s surface. The most lustrous pearls are notably bright and shiny, reflecting mirror like images, and are highly desirable. In addition to excellent luster, the finest quality pearls have a surface that is smooth, clean and blemish free.
What kind of pearls should I buy?
When making comparisons, keep in mind that freshwater pearls may not be as round as Akoyas, and their luster is often not as shiny or sharp. Freshwater pearls are available in a greater variety of natural colors and tend to be less expensive. In larger sizes, top quality white South Sea and black Tahitian pearls are far more valuable than freshwater pearls.
What is the best way to clean pearls?
People often ask about the proper care and cleaning of pearls. The preferred cleaning method is to gently wipe the pearls with a soft, damp cloth after each use. If a more thorough cleaning is needed, use a mild soap solution (such as Woolite in warm water), rinse completely, and then lay the pearls flat to dry before storing. The Mohs scale of hardness ranks pearls at a relatively soft 2.5 to 4 on a scale of 10, with diamonds holding the top spot at 10. Due to this delicate nature, “last on, first off” are good words to live by when wearing pearls. One should avoid contact with cosmetics, hair spray, perfume or household chemicals as much as possible. If the knots have become frayed or soiled, or there is too much movement of the pearls in between the knots, it is time to take them to a reputable jeweler and have them re-strung.
Sharon S. Axelson
Graduate Gemologist, Gemological Institute of America
Certified Gemologist Appraiser, American Gem Society
- View pearl jewelry from our Jessop’s Collection -