Pearls are a wonder of nature. They are formed inside of the soft tissue of a living mollusk that deposits calcium carbonate layers concentrically over and over again. The prefect pearl is completely round, smooth and lustrous. They do come in other shapes, known as baroque pearls. Almost all species of mollusks are capable of producing pearls, but these others have less shine and spherical shape. Pearls have been highly prized for centuries in many cultures. Both natural & cultured gem-quality pearls are nacreous and iridescent.
The value of a pearl varies. There is no standardized grading system for pearl quality, but there are a number of factors that help determine the value: pearl type, rarity, size, shape, color, nacre quality and luster, and weight (for natural pearls) or size (for cultured pearls). You can learn more about the different kinds of pearls here in our pearl guide. And while it’s not exactly a pearl price guide per se, it should give you some idea of what to expect in terms of value.
Wild pearls or natural pearls occur spontaneously in the wild, but are extremely rare and valuable. Hundreds of pearl oysters have to be opened, and therefore killed, to find even one wild pearl. This was how pearls were found for centuries. Their value is determined by size, shape, color, surface and symmetry. Natural pearls are graded differently than cultured pearls; they are graded by carat weight and not by millimeters. The larger the pearl the more valuable it is.
Cultured or farmed pearls from pearl oysters and freshwater mussels make up the majority of pearls sold. They come in two types, Saltwater & Freshwater. To create a pearl, a tiny piece of mantle tissue from a donor shell is put into the host shell, and sometimes a bead nucleus is added. This causes a pearl sac to form where the calcium carbonate is distributed.
Saltwater, beaded, cultured pearls are South Sea, Tahitian & Akoya Pearls. South Sea pearls are the most sought after pearls because they are the largest & rarest, followed by Tahitian pearls (black pearls). Tahitian pearls are considered to be of value because they are uncommon. The pearl oyster that creates the Tahitian pearl is more abundant than the elusive & infrequent pearl oyster that creates South Sea pearls.
South Sea pearls are prized for their luster & size. Their colors can be white, silver, pink, gold, cream or a combination of these with overtones that are the same as the oyster shell itself. Akoya pearls are grown from small oysters. They are known to be nearly identical in size, shape, color and quality. All of these pearls types can only be grown with one pearl in an oyster at a time.
Freshwater pearls were originally started in Japan, but since then China has become the world’s largest producer. Freshwater pearls are generally irregular in shape but new farming and pearl-enhancement technology produce more round pearls in a new array of colors. Freshwater, non-beaded, cultured pearls can be implanted up to 25 at a time in a single mussel. These completely saturate the market.
The five Virtues of pearls
Akoya pearls are left to grow for 1 year and reach from 6-8.5mm. Tahitian & South Sea pearls are left for 2-4 years and can reach 13mm. Freshwater pearls are left for 2-7 years and can range from 3-13mm. The larger the pearl the more valuable it is. To create larger pearls they have to be left inside of the mollusk for longer.
Pearls come in eight basic shapes:
Round– Perfectly round pearls are the rarest and most valuable shape.
Semi-round– used for necklaces or in pieces where the pearl can be disguised to look more rounded.
Button– used in pendants or earrings where the flat back can be covered and it looks like a rounder larger pearl.
Drop– often used in pendants, earrings or as the focal point of a necklace.
Pear– also often used in pendants, earrings or as the focal point of a necklace.
Oval– once again, often used in pendants, earrings or as the focal point of a necklace.
Baroque– valued for their unique and fascinating shapes.
Ringed or Circled– have a concentric ridges along the middle of the pearl.
White and black pearls are the most popular, but there are also silver, gold & pink. Pearls also have tints or undertones that can make it have a glow. For example, a pearl can look white but when studied and light is reflected off of it, it can give off a hue of pink, green or blue. Black pearls are rarely black, they can be shades of green, purple, blue, grey, silver or peacock. The very best pearls have a metallic mirror-like luster.
For cultured pearl experts, luster is the single most important indicator in evaluating pearl quality. Luster is what separates the superior from the inferior and the extraordinary from the ordinary. The luster of the pearl comes from the reflection (change in direction of a wave passing from one medium back to the same), refraction (change in direction of a wave passing from one medium to another) and the diffraction (when a wave meets an obstacle) of light through the translucent layers. The more layers and the thinner they are, the better the luster. The iridescence of a pearl is caused by the overlapping of layers- they break up the light falling on the surface.
Surface or Complexion
Nature is not normally flawless and as a mollusk creates a pearl where often, the layers of the nacre do not get applied evenly. This causes bumps that can appear in the pearl surface. When judging the complexion (the trade uses terms such as ‘blemish’, ‘spotting’, and ‘cleanliness’), remember that pearls are made by live oysters in a natural environment. There are many uncontrollable effects that create the surface. The most valued pearls are smooth and come with a higher price tag.
Akoya pearls are usually bleached to remove dark spots and made to look even. Irradiation makes a pearl grey-blue or grey-black colors. In their natural state, freshwater pearls are not marketable for jewelry and need enhancements. After cleaning and sorting, they are pretreated in a warm and cold chemical solution. Unless they have a strong color, they are bleached. Freshwater pearls can be dyed to make different hues, like yellow, green, blue, brown, pink, purple, or black. Pearls that are naturally colored, rather than color enhanced by artificial means, will add value to the pearl. Lastly, they are polished with a mixture of cornmeal and wax.
Real Vs. Fake
The way to tell the difference between real and fake pearls is by judging the surface and evaluating how textured it is. Real pearls will have a slightly uneven, rough surface. It is a trick to rub your teeth lightly over the surface to be able to feel the texture. Faux pearls are made from glass or plastic and are totally smooth. Real pearls also vary in size, color and luster and don’t look uniform.
Pearl Care & Cleaning
You should be gentle on your pearls since they are naturally soft. Try not to get lotions, hairspray and perfumes on pearls because this can deteriorate the luster. Wipe them down before putting them away in a soft cloth bag, not plastic. See more details about pearl care.
If you wear your pearls often we recommend getting your strand restrung every 5 years. Are you finding fraying knots and stretched out strands? Come in for a pearl necklace repair. We are also happy to re-attach pearls earring together or replace a missing pearl from an earring. We do it all! Read more abut our repair services.