Natural pearls were once only associated with royalty because it would take the average individual an entire lifetime to be able to afford a pair of small pearl earrings. Due to the high prices of rare natural pearls and the increased market demand, the process of cultivating pearls was created.
Natural pearls are those that are formed without the help of mankind, and are one hundred percent solid nacre. One false impression about natural pearls is that a grain of sand irritates the oyster, which causes it to produce a pearl. The true process involves a piece of food or a floating object that gets caught in the shell sac of an oyster. This causes an irritation within the oyster by which the object is then coated with a substance called nacre.
Cultured pearls are those that are formed by the help of mankind using an artificial irritant. There were three individuals that were involved in the development of cultured pearls; however, Kokichi Mikimoto is most notable for this cultivation process. Mikimoto perfected the process by determining that the best artificial irritant that would not cause the oyster to die was a piece of shell from a mussel found only in the United States.
A pearl’s structure is composed of an irritant, nacre, and conchiolin. The oyster first coats the irritant with nacre, then coats it with an adhesive like substance called conchiolin and continues to alternate back and forth between the two substances. Nacre is composed of calcium carbonate that turns into aragonite crystals. These aragonite crystals are arranged into prismatic crystals that produce the beautiful luster of a pearl.
When one is looking to buy pearls, there are several factors that one needs to observe before making that final purchase. These factors include: size, shape, luster, nacre thickness, blemish, color and matching. Size is the easiest when it comes to grading because it is based on personal preference whether one wants big or small sized pearls. All pearls are measured in millimeters and it is advised that one always use a plastic millimeter gauge in lieu of a metal one to avoid scratching the pearls.
The next characteristic to look for when purchasing pearls is shape. Pearls come in all different types, from perfectly round, off round, semi-baroque, baroque, potato, and stick. The easiest way to tell if your pearls are round is to roll them on a table; if they roll in a straight line your pearls are perfectly round. Luster, another purchasing characteristic to be aware of, is light radiating off the aragonite crystals caused by the thickness of the nacre and the uniformity of the nacre layers. Nacre thickness is the most important factor when it comes to pearls because this is what gives them their beauty. There are two ways to determine the nacre thickness; the first being if the pearl has a metallic looking surface. The second is to use a 10x loupe to examine the thickness of the nacre through the drill hole.
Pearls are sought after because of their beauty. When one has a heavily blemished set of pearls, the luster is affected making them less attractive. It is virtually impossible to match pearls that are heavily blemished. Color, like size, is based on personal preference. Pearls come in different colors from rose, white, silver, cream, gold, and blue/gray. The last characteristic is matching. When purchasing pearls, consumers should be certain they match up in size, shape, color, luster, nacre thickness, blemish, and color. The best way for one to observe all of these characteristics is to place the pearls on a white cloth or piece of white paper.
To minimize damage to pearls, always purchase pearl jewelry that has knots in between each individual pearl. Pearls are knotted to prevent them from rubbing against each other and causing damage. Pearls should be restrung every two years whether they are worn frequently or rarely. Other precautions one should take to avoid damage to pearls are the following: remove pearl jewelry when applying lotions or using hairspray, do not wear pearl jewelry in a pool, hot tub, or shower due to the chlorine in the water, and clean your pearls with a damp cloth only.
Salt-water pearls are more valuable then freshwater pearls. There are two ways to identify which kind of pearl one is buying. The first factor are the hole sizes within the pearl. The size of the hole drilled into a freshwater pearl is going to be much smaller then the hole of a salt-water pearl. The second are the knots in between each pearl; the majority of freshwater pearl jewelry do not have knots, whereas all salt-water pearl jewelry has knots.
Like most gems, pearls face imitations and treatments. The imitation pearls that one will encounter are plastic, glass, and essence d’orient. Determining whether one has an imitation or a real pearl is much easier then one would think. The first test to determine this is to rub the pearls against your teeth. If the pearls feel gritty, they are real. If they feel smooth, the pearls are imitations. The second test is to examine the hole. If it appears to be smooth, then the pearl is real. If the hole appears rough, then it is an imitation. Essence d’orient or shell pearls are glass beads with fish scales glued on them. If one has a chance to purchase essence d’orient, know that the fancy name does not mean a luxury kind of pearl.
The treatments that are applied to pearls are vapor deposits, bleaching, dying, and irradiation. Vapor deposit is the process of improving the color of the artificial irritant (i.e. shell or “starter bead”) to prevent the color of the starter bead from coming through; especially when the nacre of the pearl is thin. Bleaching is the process of placing off-colored pearls in a boiling pot of bleach for ten hours making them white in color. Next is the dying process. This can take away from the luster of the pearls; however it allows for inexpensive colored pearls as opposed to expensive natural colored pearls. The final treatment, irradiation, involves turning the starter bead black to improve the color of black pearls.
The cultured pearls on the market today are just as beautiful and full of luxury as the natural pearls once worn by royalty that is, at a price that does not take a lifetime to save up for.