This page is designed to help you the consumer obtain a better understanding of pearls. Pearls come in all different shapes, sizes, colors, and qualities. Pearls can be formed naturally without the help of humans, while others are only produced with a helping hand from mankind. The next few paragraphs won’t make you an expert, but they will educate, making for a better experience while shopping for pearls.
Shape: When most people close their eyes and think of a pearl they picture a perfectly round shape. Though most pearls are “round” in shape, pearls come in lots of different shapes, including baroque, button, and drop, just to name a few. A perfectly round pearl is rare and extremely expensive, you will see some deviation in most round pearls.
Size: Just like diamonds, pearls are measured in millimeters. Pearls can range in size from under 1mm to over 11mm. The majority of pearls on the market today range from 6.0 – 7.5mm for a traditional pearl necklace. Also like diamonds, the larger the pearl the rarer and more expensive it is. Most Tahitian and South Sea pearls measure 10.0mm or larger. It may take double the time- 4 to 6 years- for a large pearl to be created, versus the normal 2 to 3 years for an average size pearl.
Color: Most people picture pearls as white in color and most are; however they can be other unique colors such as black, blue, green, silver, gold, or pink. Some pearls appear to have more than one color. This is called “overtone”. Overtone is a secondary color picked up with the main color of the pearl. An example of this is white pearls that have a rose/pink color. White is the main color and the pink/rose is the overtone complimenting the white color. Other factors determining color are orient and iridescence. Iridescence is the sparkle achieved when the pearl is rotated as the light reflects through the layers of nacre.
Surface Quality: As a pearl forms inside the mollusk, layers of nacre are established. Unfortunately, there is no guarantee that each nacre layer will be completely smooth. Sometimes small bubbles, indentations, or blemishes may form. In the trade these blemishes are acceptable and may reduce the value slightly. Cracks and small chips in the nacre are frowned upon and have a much greater effect on the overall value of a pearl.
Nacre Thickness: As stated previously, nacre forms the pearl while it is inside the mollusk. Nacre has multiple layers and each layer can have a different thickness and uniformity. How these layers form with each other leads to the final appearance and overall value of the pearl.
Luster: Diamond isn’t the only stone that reflects light. Luster is the reflection of light off the pearls nacre. A pearl’s luster is dependent on a pearls nacre thickness and layers. The thicker the nacre layer, the better the luster, and the more valuable the pearl. When shopping for pearls, take a close look at an individual pearl on a strand. Depending on its luster, look for your own reflection, and how crisp or clean that reflection is. The crisper your reflection, the better the luster.
Matching/Uniformity: Most multi pearl pieces are matched for uniformity. Matching means the pearls are inspected in all areas, including shape, luster, size, and color, in order to ensure all the pearls look the same. The better the match, the more valuable the piece.
Pearl Varieties: Pearls can grow in both freshwater and saltwater environments. Some pearls are grown naturally without the help of humans, and some are aided in the process. The following is a breakdown of the different types of pearls you will find throughout the jewelry industry.
Freshwater: Most cultured pearls are bead nucleated. This process involves a small bead that is inserted into the mollusk in order to start the process of growing the pearl. Freshwater pearls do NOT go through this process. A graft of mollusk tissue is inserted into the mollusk, allowing the nacre to form. This process, and the freshwater the mollusk lives in, determines a freshwater pearl.
Akoya: The pearl that everyone pictures when they think of a pearl is the Akoya. Akoya are traditionally harvested in Japan or China, and are cream to white in color, varying in size from 2 to 10mm. Because of their uniformity and round shape, Akoya are one of the best pearls to use in jewelry.
Tahitian: Contrary to popular belief, Tahitian pearls are not dyed. They obtain their color from their host, the black lipped oyster, located in the lagoons of French Polynesia. Tahitian are usually thought to be black in color; however, they come in a range of blacks, silvers, and peacocks. Unlike traditional Akoya pearls, Tahitian are quite large in diameter, ranging from 8 to 18mm. Most are uniform and round, though some can show a nacre ring.
South Sea: The pearls of the South Sea are some of the largest pearls in the world, ranging in size from 8 to 18mm, and for good reason: the pinctada maxima oyster that produces the pearl is one of the largest white lipped oysters in the world, measuring up to 12 inches in diameter. The oyster is located in the deep seas, making the cost of obtaining each pearl quite expensive. Most South Sea pearls vary in color from silver, silver-pink, ivory, and gold.
Mabe: Unlike most pearls, Mabe pearls do not form within the tissue of the host mollusk; instead they grow on the inside of the shell. Hemispherical in shape, Mabe pearls are unique, not only in the way they are harvested, but also in that the nucleus is replaced with resin, and a flat piece of mother of pearl is added to replace the backing.
Keshi: Keshi or Seed pearls are irregular baroque pearls that are produced during the formation of the main pearl within the mollusk. The terms Keshi actually means “poppy seed” in Japanese. When the mollusk rejects a piece of the mantle, or bead nucleus, the pieces still remain within. As they irritate the mollusk, nacre forms over the pieces, eventually creating a Keshi pearl in a unique shape.
Care and Cleaning: As a general rule of thumb, pearls should be the last thing you put on and the first thing you take off. Makeup, hairspray, and perfume all can damage pearls, causing spots, blotches, discoloration, etc. Wearing pearls next to other pieces, metals, or stones, can lead to scratching and dulling of the pearls surface.
Pearls prefer the human bodies natural oil. Wearing your pearls helps keep the luster in good shape, so wear them often. Before storing your pearls be sure to take a soft cloth and wipe them off. You can clean pearls under warm water, however this is not recommended with pearl strands or 1/2 drilled pearl pieces. Water will deteriorate the string used on the strand and also wear away the pearl epoxy used on 1/2 drilled pearls.