Pearl color - the main color of the pearl, usually shades of white, cream, gold, or black. Translucent colors called overtones can give the pearl additional iridescence.
Pearl luster - how the pearl looks when light moves through it. Each light acts as a mirror and reflects light, which gives the pearl its coveted glow. Luster is what makes a pearl beautiful, and is the most important trait.
Pearl surface - since they are natural gemstones, pearls have small blemishes, spots, indentations, or other small imperfections.
Pearl size - a pearl is measured in millimeters (mm) among its diameter, with 25.4 mm = 1 inch. Large pearls are rarer than smaller pearls, so they are more expensive.
Nacre quality - the most valuable pearls are made of thin and even mother-of-pearl layers.
Pearl shape - the most coveted is perfect round, which are extremely expensive.
Types of Pearls
Akoya pearls from China or Japan are supremely shiny and usually white with silver or rose overtones. Akoya pearls, the original cultured pearls, are consistently round and grow to be between 2 and 13mm.
Tahitian pearls are actually cultured in French Polynesia from black-lipped oysters. These mysterious and exotic pearls are naturally colored blue, black, silver or gray with green, purple or blue overtones. Tahitian pearls are between 8 and 16 mm wide and the most valuable colors are black with green overtones.
South Sea pearls are grown in white-lipped oysters. These milky pearls are known for being large, ranging from 9 to 17mm and are naturally colored white, gold, silver, cream and champagne hues.
Freshwater pearls are farmed in rivers and lakes, mostly from China. They grow between 2 and 13 mm, come in both round and irregular shapes, and are more affordable than saltwater pearls. Freshwater pearls naturally are white, but jewelry makers can dye them to create high fashion jewelry.
Mabe pearls, or blister pearls, grow against oyster shells so their backs are made of iridescent mother of pearl. These pearls are lustrous and less expensive than round pearls.
Shape influences a pearl's quality grade and price.
A pearl usually maintains the shape of its irritant, so pearl farmers insert round nuclei in oysters to try to create perfectly round pearls. Only 5 to 10% of the cultivated pearls grow to be even and round.
Pearls are classified as being spherical, symmetrical or baroque.
Round pearls - the most coveted, rare and expensive pearls are perfectly spherical.
Near round pearls - round but not perfect spheres. They look like perfectly round pearls to the untrained eye, but are much less expensive. Near round pearls are classified as spherical pearls.
Button pearls - symmetrical pearls with a flattened shape, often used for stud earrings.
Drop pearls - symmetrical teardrop or pear-shaped pearls. Drop pearls are typically used as pendants and earrings.
Baroque pearls - irregular or non-symmetrical and do not have a defined shape. They are the least valuable but can have high luster and look very beautiful in artful settings. Natural pearls are often baroque.
Circle pearls - baroque pearls with rings around their diameters. Most common in South Sea pearls and Tahitian pearls.
A pearl's luster can be damaged by cosmetics, hairspray and perfume. Avoid applying perfume where pearls will be worn and put on pearl jewelry after makeup and hair is complete.
Use a soft, damp micro-fiber or lint-free cloth and mild soap to gently wipe off body oil, perspiration, cosmetics and residue after every use. Thoroughly clean pearl jewelry periodically, but do not use a sonic jewelry cleaner.
Pearls are delicate and should be stored separately from other jewelry to prevent damage. Wrap pearls in soft cloth or store in a soft pouch or lined box to prevent scratches, dents and cracks.
Restring annually if pearl jewelry is worn often, or restring every three years if worn occasionally. Restring with silk or nylon thread. Knotting the string between the pearls will minimize friction and prevent loss if the string breaks.
It will take several hours for new or restrung pearls to relax and hang properly.
Pearls are the only biological gemstone and are prized for their intense, milky luster and shiny iridescence.
Pearls are created when an irritant, like sand, gets stuck in a mollusk's soft tissue. The mollusk responds by covering the irritant in nacre. The pearl grows in size as the nacre builds new layers.
Natural pearls are so rare and expensive because only a small number of oysters will produce a jewelry-worthy pearl and be discovered in the wild.
Only nobles and the extremely wealthy could possess pearls for most of recorded history.
Pearls only became assessable to everyone when the Japanese discovered a cultivating method in the early 1900s.
Cultivated pearls are not artificial. Cultivated means the pearls were made by placing an irritant into the shell so the mollusk produces a pearl.
Almost all commercially sold pearls are cultured.
Find out if pearls are genuine by rubbing them against your teeth. Real pearls feel gritty while faux pearls will slip without any resistance.
Pearls have become a symbol of natural beauty, purity, taste and refinement. They are romantic jewelry gifts and embody vintage, old-Hollywood glam.