The pearl is the oldest known gem, and for many centuries it was considered the most valuable. What sets the pearl apart from most other gems is that it is an organic substance derived from living oysters and mollusks.
There are two main types of pearls in the market today; those that come about naturally and those that are cultured. Naturally occurring pearls hold a significant value due to their rarity, however, in terms of quality; both natural and cultured pearls are of equal quality. Pearls are very unique and require no faceting or polishing to reveal their natural beauty. Today, pearls are still considered to be valuable gems and are in high demand in the Jewellery industry.
The overall quality and value of natural or cultured pearls are reflected in characteristics which include the color, size, luster, shape, surface quality, and nacre quality of a pearl.
The Six Value-factors of Pearls
Both natural and cultured pearls come about in a wide range of colors and hues including white, yellow, pink, blue, green, violet, and black. The tone of pearls also occurs in a broad range from light to dark. The Color factor of pearls is not one that significantly affects the value of pearls as it is generally a matter of preference.
Pearls vary in size from 1mm to about 20mm. The most common size of cultured pearls range between 6- 7.5mm. To date, the largest pearl recorded is a 26.95mm baroque south sea pearl. The value of a pearl is in relation to its size; the larger the size of a pearl, the higher its’ value.
Luster refers to the intense glow that comes from within a natural or cultured pearl, giving it exceptional beauty. Luster is considered to be one of the most importance value-factors of Pearls. The glow is a product of light entering the pearl and reflecting back through the layers of nacre. The quality of a pearl’s luster is directly related to the smoothness and symmetry of the nacre layers. A pearl with a dull or diffused luster is considered to be of poor quality. A pearl with high luster exhibits a sharp and bright reflection, making it higher in value.
Flawlessly round pearls are regard as the most valuable shape for pearls, as there are extremely rare to find in nature and are difficult to culture. Only 6-10% of harvested pearls result as evenly round. Most pearls occur in other shapes as pear, oval and other irregular shapes known as baroque. Although perfectly round pearls are the most value, all other shapes of pearls are also valued and cherished in the jewellery industry.
Surface characteristics on pearls affect the overall surface quality. Numerous blemishes and scratch on the surface can have a negative effect on the beauty and value and durability of the pearl. Pearls with little to no surface characteristics are considered to be most valued, when all other variables are held constant.
Nacre refers to the smooth layers that make up the pearl and give it beauty. Nacre quality influences the luster as well as the durability of the pearl. The thinner the nacre, the more visible the core of a pearl is, giving the pearl a dull and chalky appearance. The thicker and smoother the nacre, the brighter the pearl is, giving it more value.