Genuine pearls are solid and substantial, making them heavier than their faux counterparts. Try this pearl test; hold a loose pearl in your hand and feel its weight. If a loose pearl is light in proportion to its size, it is probably an artificial stone.
Real pearls are heavy compared to most fakes. They should feel like they have some weight to them, compared to a hollow plastic bead. The surface will feel gritty. Gently rub two pearls in a strand together.
A real pearl will have more mass than an artificial one which means it has a much higher density and should weigh slightly heavier when compared with another pearl of the same size. Real pearls are heavier than artificial ones, weighing about one-fifth as much, and often contain lead on the inside.
Weight: Lastly, you can tell real pearls from fake is by feeling their weight. Fake plastic pearls are light when compared to real pearls. That said, counterfeiters have increased their level of deceit by making fake pearls from heavier materials (such as glass) to make their weight the same as authentic pearls.
The weight of pearls is most often indicated within a 10th of a gram. In the past the unit of weight used to be the grain which represents ? carat (0.2 gr).
Real pearls will have a strong and iridescent shine, while fake pearls may appear dull or cloudy. Also, rub two natural pearls together; they are real if they make a gritty sound. Lastly, examine the surface of each pearl; real pearls will often have blemishes or small bumps on them that are not found on faux ones.
Freshwater pearls are cheaper because they are easier to extract, making sea pearls more valued. Why? Sea pearls are larger, more beautiful in shape, luster, smoother surface and, of course, much more expensive than freshwater pearls.
A natural pearl may show growth lines where concentric layers of nacre have been added. Cultured pearls on the other hand will appear to have a perfectly rounded nucleus that's surrounded by a halo of conchiolin and finally a thin outer layer.
Pearls with particular brand names will also retain (and even increase) their value over the years; vintage Mikimoto Akoya pearls that still have their original clasp, box and papers to establish provenance are very highly sought after today and continue to fetch premium resale values.
Average weight of the pearls = 25 grains. This compares well with the actual weight of 47 grams for the entire necklace.
The combination of surface brilliance and a deep-seated glow, the luster of a good-quality cultured pearl should be bright, not dull. You should be able to see your reflection clearly on the surface of a cultured pearl. Any pearl that looks too chalky or dull indicates low quality.
Pearl Size
Tiny seed pearls can be smaller than 1mm, while South Sea pearls, as large as 20mm, have been found. If all other quality factors are equal, the size of a pearl will determine its value.
Both natural and cultured pearls have textured surface due to their layered nacre structure. So when you rub the pearls lightly against each other or on your front teeth, they feel a little gritty. Fake or imitation pearls, however, usually feel smooth or glassy.
A real pearl almost always has a clear outer nacre layer, while fake pearls have thin layers of artificial nacre or lack them entirely. If your pearl has a drill hole, you can check for nacre by peering in with a magnifying glass.
To try it for yourself, put a drop of vinegar on the pearl or submerge the pearl in a small cup of vinegar. If you can see bubbles forming from the release of carbon dioxide in the chemical reaction, your pearls are authentic.
Some of you may be concerned that if their pearls turn yellow, this indicates that they are fake. Contrary to popular belief, imitation pearls very rarely turn yellow due to their composition of plastic and ceramic. Pearls that begin to yellow indicate that they are organic and subject to change.
Round and near-round shapes are more common in saltwater pearls than freshwater pearls, thanks to the nucleus that is implanted in oysters. Therefore, between an Akoya and a Freshwater pearl, all qualities having the same, the freshwater may command a higher price than its saltwater counterpart.
Akoya Pearls: These pearls represent some of the best cultured pearls available today. Known for their metallic luster and perfectly round shape, they are regarded as the classic white pearl. While most Akoya pearls are farmed in Japan, China and Vietnam both produce Akoya pearls as well.
The 22K to 24K Golden tone is a "Very Deep" natural Golden color. Golden South Sea pearls featuring the 22K to 24K hues are the rarest and most valuable (all other factors being equal).
Japan is the acknowledged leader in Akoya pearl production – known to produce the best, most consistently beautiful Akoya pearls in the world.
The larger the pearl the more valuable. Pearls can range from sizes as small as 1mm to the world's largest pearl which is over 650mm and weighs 34kg (approximately 75lbs). Most pearl jewelry, however, is usually in the range of 3mm to 18mm.
Astrology says that the people whose zodiac signs lords are Mercury, Venus, Saturn and Rahu should never wear pearls. Pearls harm the natives of these zodiac signs. This means that people of Taurus, Gemini, Virgo, Capricorn and Aquarius ascendant should not wear pearls.