While much of the process of choosing pearls is subjective, and depends on the wearer’s taste, there are a few questions to ask that will ensure that the pearls you choose will be of the highest quality. Just like diamonds have their “4C’s”, pearls have common properties that should be considered as you shop.
A pearl’s color is more a matter of personal taste than one of quality, but naturally colored pearls will typically weather trends and fads better than those that have been artificially dyed. Beware especially bright or garish pearls, as these are almost certainly the result of manmade color processes and the dye can be prone to fading or even wearing off onto skin or clothing. Strong colors may sometimes indicate a lower-quality pearl, as the dye may have been used to disguise unsightly color variations in the surface of the pearl.
Orient and Overtone
There are very small differences between orient and overtone. The orient of a pearl is the beautiful iridescent shimmer of color that spreads across its surface. Often, this causes a ‘rainbow’ effect on the surface of the pearl. This color is not the same as the color of the pearl itself, but the iridescence that may seem to dance and move across the pearl as you turn it. In contrast, the overtone of a pearl is the secondary impression of color from a pearl as it is viewed against a white background. For example, a black pearl may seem to have a subtle blush of green. This color, unlike the orient, does not shimmer, but may differ depending on which side of the pearl is viewed, due to the refraction of light within the pearl.
Examples of Overtone on a White Pearl
Examples of Overtone on a Black Pearl
Black Pearls Displaying Excellent Orient
The larger the pearl, the longer it had to remain in the oyster’s shell, and as a result, these are usually more costly. Very large pearls are a rarity, due to the cost of producing them. Consider that the oysters must be kept healthy and safe from predators, parasites, and destruction of their natural habitat for several years while the pearl is allowed to form. Additionally, the extra time in the shell increases the likelihood of blemishes forming on the pearl as small imperfections in the nacre are magnified as they are coated. Flawless pearls of a large size will command very high prices.
Surface indicates the perfection of the exterior of the pearl itself. Higher quality surfaces have very few marks, bumps, ripples, or blemishes, indicating that the oyster was very well cared-for during the cultivation process. Pearls that show little to no variation in their surfaces will typically cost more than those with a few marks here and there.
Regularity refers to the shape of a pearl. The more spherical the pearl, the more regular it is said to be. No pearl is perfectly round, but some come close to being spherical. The best pearls are typically smooth and even. Do not pay for a pearl that is absolutely spherical and has no defining marks unless it is certified, as these are probably synthetic, and therefore of low value.
A pearl’s luster, or shine, is determined by the layers of ‘nacre,’ the substance pearls are made of, that coats its central nucleus. Usually, more nacre results in higher luster. The surface curvature of a pearl can also have an effect on the luster, as light passes through the delicate outer layers and refracts off of the aragonite crystals in the pearl, giving the pearl its signature glow. This causes the highly desirable translucent appearance that very fine pearls display.
A genuine pearl will typically show minor variations in shape, color, and surface. Truly perfect pearls are rarely real, but may be simply convincing fakes. One way to test their authenticity (although this test can be fooled) is to gently rub the pearl on the edge of your tooth. Genuine pearls will feel very slightly gritty, due to their crystalline structure, while faux pearls and glass pearls will feel smooth and silky. The exception to this rule is composite, or “shell” pearls, which are created by grinding low-quality pearls into a powder and then reconstituting them using epoxy or acrylic. Due to their nacre content, these will feel gritty to the teeth, but since they are usually perfectly round, they are easy to spot and avoid.
Other fake pearl types to look out for:
- Plastic: Ultra-shiny, easy to chip the paint. Very lightweight. Usually unknotted. Smooth to the tooth.
- Glass: Higher quality, usually knotted in between and heavy. Look for paint flaking near the drill-holes. Smooth to the tooth.
- Mallorca: A specific variety of glass pearl, very high quality and usually difficult to identify. The paint is very similar in luster to real pearls, but if on a strand, will be perfectly uniform. Smooth to the tooth.
Check out our post on Real vs. Faux pearls for more info on Authenticity!