How do pearls grow in a shell?
We all have an idea of where pearls come from. But how much do we know about its cultivation in the modern world? 
March 28, 2023 256 0 –> When buying rings with pearls, earrings or a chain, some buyers ask the question: “Are these pearls real or artificial?” At the same time, sellers themselves are often confused about clear answers. Let’s start with the fact that this is not a completely correct question. Natural (wild) pearls are a real miracle of nature, the reserves of which on the market are almost exhausted. Many may think that in this case, buyers are offered artificial stones. But it is not so. There are wild pearls, there are cultured pearls, and there are artificial pearls. And the last two types are not identical concepts. In this article, YuK decided to understand the terminology, varieties of pearls, as well as methods of growing them. To ensure that there is no confusion for our customers. What stones are presented in jewelry, how they are grown, and who they are – the world’s pearl producers – read about this in our new article. 
How are pearls formed?
The birth of a pearl in a mollusk shell is a real magic of nature. It is impossible to predict what the pearl will be like. This is its originality and at the same time uniqueness. In Greece, there were once legends that pearls were the hardened tears of mermaids. But in reality everything is much more prosaic. The mollusk perceives any grain of sand that gets inside as a stranger and begins to stubbornly cover it with layers of nacre. As a result of this protective reaction, a white ball called a “pearl” is born. At first, to get a pearl, divers descended to great depths and opened hundreds of shells, which subsequently died. At the beginning of the 20th century, a more humane method was invented. Stones began to be grown on special farms. There they created conditions as close as possible to natural ones.
How are cultured pearls grown?
Artificial pearls in earrings, rings, and pendants are created without the participation of oysters. The championship in this area belongs to the Japanese, who have learned to create pearls from scrap materials. At first they made imitation from glass and crystal, but such jewelry was quite heavy and uncomfortable to wear. Later, they resorted to lighter materials at hand, such as cotton. The fiber was impregnated with pearl essence and given the desired shape. Modern technologies make it possible to create pearls in the shape of an oval, cube, drop, heart, etc. It can also be given any color (from pastel to bright neon). When making it, craftsmen use beads made from mother-of-pearl shells, as well as the famous “majorica”. The latter are made from alabaster balls, which are covered with thin layers of mother-of-pearl. It is very difficult to distinguish such pearls from natural ones. Among the leaders in the world market are also imitation pearls Shell Pearl (USA). It is created on the basis of natural mother of pearl. When making it, craftsmen use special sea shells (tridacnis). They are crushed into small pieces, which are then polished to a perfectly smooth shape. To bring the imitation as close as possible to natural pearls, manufacturers also make baroque Shell Pearl of irregular shape. It is convenient to work with artificial pearls, and most importantly, it is resistant to external influences. Another important bonus is its reasonable price.
How are wild pearls grown?
Wild pearls are of organic origin. It is produced by mollusks inside their shells and consists of layers of mother-of-pearl. At first, pearls were mined from the depths of the sea. For these purposes there were special people – divers who dived to great depths without any auxiliary equipment. It happened that we had to do up to 30-40 such dives a day! By the end of the 19th century, wild pearl fishing led to the destruction of entire colonies of mollusks. To get 3-4 high-quality pearls, it was necessary to open up to a ton of shellfish. Subsequently, they all died after autopsy. Over time, they learned to cultivate pearls in order to preserve the population of mollusks, as well as to increase the scale of its production. Today it is rare to find wild pearls in jewelry, except perhaps in vintage ones. Its value is great, so this pleasure is not cheap.
How are cultured pearls grown?
Many people mistakenly call cultured pearls artificial. In fact, these are natural pearls that are grown in natural conditions under human control. Today it occupies 99% of the world market. The process of growing such pearls is complex and painstaking. On average it takes up to 3-8 years. At the same time, people are practically deprived of the opportunity to influence the process in any way: it is unknown whether the implant will take root, how the pearl will grow and look. This is a high risk for business. The final result mainly depends only on nature.
How are freshwater pearls grown?
Freshwater pearls grow in fresh river or lake water. In China, for example, entire rice fields are allocated for this purpose. “Pearl” farmers constantly monitor water temperature, its composition and pH. During the ripening process, shellfish pearls must be turned over from time to time so that the pearl does not turn out “one-sided”. Freshwater pearls are very popular due to their variety of shapes, colors and sizes. Their average size is from 4 to 6 mm. The freshwater pearl mussel lives up to 30 years. During this time, several “generations” of pearls can grow in it. Typically, pearls “mature” from 3 to 5 years. Do you know how many pearls one freshwater shell usually “bears”? You won’t believe it: from 15 to 40!
How are saltwater pearls grown?
Sea pearls are born in the bodies of mollusks that live in warm sea waters. The most popular elite types are Akoya (in the seas of southern Japan) and South Sea pearls. Such pearls are tens, or even hundreds of times more expensive than river pearls! Why is that? Because salty sea water gives pearls a more beautiful shine than fresh water. And the shape is rounder and smoother. But there is one “but”. Sea pearl mussels are terribly capricious. They must certainly live at a certain depth, in water with a constant chemical composition and t. When the water changes by just 2 degrees, the mollusk’s body begins to produce acid and the pearl in it deteriorates. Thus, farmers can easily lose the result of many years of work in one day. 
31 UAH 440 UAH 
8 UAH 900 UAH 
9 UAH 400 UAH 
80 UAH 280 UAH 
10 UAH 000 UAH 
19 UAH 518 UAH 
26 UAH 789 UAH 
27 UAH 620 UAH 
34 UAH 560 UAH
Methods of growing pearls
There are two main methods: nuclear (a seed nucleus is placed in the shell to obtain sea pearls) and nuclear-free. The second method is cheaper and is used when cultivating freshwater pearls. A pearl oyster is selected, an incision is made and an implant (part of the mantle of the donor pearl oyster) is inserted. A ball taken from a bivalve freshwater mollusk is placed next to it. After this, the pearl mussel is sent back to the lagoon, where it is grown for another 2-3 years. The balls that are placed in the oyster are carefully selected in size – they should not be too large. The oyster may die if it cannot cope with the “foreign invasion.” Some of the oysters die in the first month. Another part rejects the ball placed in them. It will take at least three years to grow more or less large pearls. After which, you can finally extract beautiful pearls. One of the external advantages is the ideal surface of the pearl, because mother of pearl grows in a thin layer on a smooth artificial ball. The nuclear-free method is simpler than the first, since it helps to grow pearls of arbitrary shape. A grain of nacre sand taken from the shell itself is used as a seed core. This method is less expensive. Most freshwater pearls up to 8-9 mm in size are grown using this technology.
How are pearls grown in the Emirates?
Do you know what the inhabitants of the Arabian Peninsula did before the discovery of oil fields? At first they made a living by fishing for pearls. This was their main business. Divers went to sea in May and returned in the fall. Then the Arabs adopted the experience of the Japanese and began to cultivate pearls on special farms. In 2005, the grandson of the last diver, Abdul Al Suwaidi, took up this task. Now the pearl factory (Suwaidi Pearls) in Ras Al Khaimah is named after him – the epicenter of pearl production in the entire Arabian Peninsula. Akoya pearls are cultivated there using Japanese technology. Thanks to its brilliance, it is considered the standard of quality in the world market. As an implant, the Arabs use mother-of-pearl balls from the shells of freshwater mollusks grown in the Mississippi River. In order for the oyster’s body to better cope with the foreign body, a piece of the mantle of one of the pearl mollusks of the same species is placed on the ball. First, pieces of the mantle are sprayed with food coloring to make them more noticeable against the background of other tissues inside the oyster. An experienced master performs up to 450 such operations per day! The final cost of a pearl depends on the color, shape and size. The largest specimens are 11 mm. Their average cost is $310.
How are pearls grown in Sweden?
Once upon a time, the largest supplier of freshwater pearls was the freshwater pearl mussel (Margaritana margaritifera), which lived in the rivers of the Baltic States, Karelia, the Kola Peninsula, Finland, Sweden, Norway, England, Ireland, and North America. Until recently, the mollusk was quite widespread. But at the end of the 20th century, its rapid disappearance began in a number of areas. This was caused not only by predatory extermination, but also by severe swampiness of the rivers, the influx of swamp water into them, and the development of timber rafting. Today Sweden is not famous for its production of natural pearls. However, there are several large companies in the country that are successfully selling artificial pearls. It was thanks to the efforts of the Swedish scientist C. Linnaeus that artificial pearls were first obtained in 1761. The scientist damaged the internal organs of the mollusk, and therefore the process of pearl formation began.
How are pearls grown in Japan?
The first person to patent the cultivation of pearls on special farms was the Japanese Mikimoto. His ideas formed the basis for the creation of the largest pearl industry in Japan. The essence of the method was to introduce a ball of mother-of-pearl into the mantle of another mollusk, where it took root and was enveloped in a pearl layer. Today, Mikimoto is the largest supplier of high-quality cultured pearls on the world market. The second largest center is in Northern Australia. In the last ten years alone, 20 tons of pearls have been grown in Japan. By 2027, the Japanese intend to raise the bar to $180 million. At the Sakaguchi Akoya pearl farm, pearls with a diameter of 3 millimeters to 1 cm are grown. Pearl harvesting occurs in December, when the water in the bay is already cold. After being collected, the pearls undergo strict selection. Only 5% of oysters produce the very ideal pearls that are put into production. It is noteworthy that in Japan, pearl products are considered a family heirloom. Traditionally, they are given to the bride before the wedding. Pearls in a shell are a biogenic solid material formed as a result of the protective reaction of some mollusks (usually sea, but sometimes river) to foreign bodies entering their bodies – this description of pearls can be found in many scientific articles. The valuable stone in question is the only formation of animal origin, the structure of which includes the mineral aragonite and conchiolin (an organic substance that forms the framework of pearls). Some historical facts.
Our ancestors have been making jewelry from pearls by hand for more than four thousand years. Today, the most ancient jewelry made using pearls has been preserved: • Figurine of Aphrodite, created according to various estimates in the 5th or 2nd centuries. BC. (kept in the Boston Museum).
• Necklace from Susa (kept in the Louvre).
• A large number of ancient products that are in private collections, and the largest pearl (Peregrina, its weight is 55,95 carats) belongs to Elizabeth Taylor.
The process of pearl formation in a shell
As mentioned above, pearls are the result of self-defense of mollusks when foreign objects enter the shell. They are unable to push out a foreign object, and to prevent damage to the body, the mollusk gradually envelops it with a special substance – mother of pearl. This happens gradually, first one layer, then the second, third, etc. As a result, the foreign body is walled up inside, it becomes smooth and does not cause any inconvenience to the mollusk. This is how pearls appear, which interest jewelers from all over the world. In some cases, for pearls to appear in the shell and their subsequent formation, there is no need for foreign bodies to enter. The “embryo” can be ordinary water, a gas bubble (regardless of the nature of its origin) or a piece of tissue from the mollusk itself. The main factor that affects the shape of the future pearl is the place where the foreign body has entered: • the “embryo” at the surface of the shell forms a so-called blister with a missing layer of nacre at the point of attachment to the hard surface of the mollusk;
• in or near the muscles, pearls of the most bizarre shapes are formed;
• formations of regular shape develop in the mantle of the mollusk. Despite the fact that theoretically all shellfish and oysters can be a source of pearl formation, in practice, some representatives of this species do not have this ability. It should also be noted that only those pearls that are created by bivalves, gastropods and one species of cephalopods have commercial value. At the same time, representatives of freshwater inhabitants “produce” formations that cost a hundred and sometimes a thousand times less than their marine “relatives”. This is due both to the physical properties of valuable stones and to the conditions of their extraction. Sea pearls are mined mainly off the coast of Sri Lanka, Japan, as well as in the Red Sea and the Persian Gulf, and river pearls are mined in Russia, North America, Germany and China.
Basic properties and valuation of pearls
The number of pearls in a shell is inversely proportional to their size, and can amount to several dozen (sometimes more than a hundred) formations in one mollusk. An important role in determining the cost of the valuable stones in question is played by the size, shape, color, origin of the pearl, as well as the purity of its surface and other individual criteria. In jewelry, a special classification system is used to evaluate stones, which, in addition to the above parameters, takes into account the thickness of the mother-of-pearl layer of pearls.
“Domestication” of shellfish
For hundreds of years, people have dived for shells to great depths (10-20 m) to get pearls. They had to do up to thirty dives a day without any additional equipment. They often got sick (the result of pressure changes) and became victims of sharks, receiving for their hard work only a small part of the real value of the valuable stones they mined. But at the end of the 19th century, a Japanese explorer created the first pearl farm. Many readers, even if they didn’t know what the enterprising Japanese came up with, most likely already guessed the principle of growing valuable stones. Foreign bodies were introduced under the mantle of the mollusks (by slightly opening the shell valve): beads, grains of sand, beads, etc. The shells were placed in special reservoirs, where ideal conditions were created for them. Then nature itself works. It takes about three years for a good quality pearl to appear in the shell; for freshwater mollusks, the period is one year less. But, given the fact that on the farm the process goes on continuously, some shells need to be implanted with foreign bodies, others are already producing a “harvest,” then there is almost always work on such farms (except for seasonal breaks). Almost 90% of jewelry presented on the world market is made from pearls, which are obtained from special farms. Most often it is called cultured; the adjective “artificial” in this case is, at a minimum, incorrect to use (after all, pearls are not made by human hands, but in a natural way). According to the main criteria, cultured pearls are in no way inferior to those obtained by divers at a depth of 20 meters, risking their lives every day, hundreds of years ago. The only drawback of the products of the above farms is a fairly high percentage of defects, but even taking this factor into account, cultured pearls are several times cheaper than those obtained without human help.
