All about pearls: how it appears
The ancient Greeks believed that mermaids' tears were turning into pearls. In the Middle Ages, people sincerely believed that pearls are the tears of orphans that angels hide in shells. The inhabitants of ancient Russia thought that pearls are mollusk eggs, and that there are shells-females and shells-males. A poetic legend has arisen in Karelia that a pearl sparkle originates in the gills of salmon. On a sunny day, the fish lowers it into an open shell, where a beautiful pearl is born from it.
The scientific explanation of the origin of pearls appeared only in the early 19th century. The real process of the appearance of pearls was no less interesting and poetic than that described in the legends.
It happens that a grain of sand or a parasite gets into the slightly open shell of the shell, which irritates and injures the delicate surface of the clam's mantle. To protect itself from pain, the mollusk begins to intensively produce nacre, enveloping them with an alien body.This process exactly repeats the actions of the mollusk during the formation of the shell.
Creating a pearl, the mollusk relieves itself from the suffering caused by a foreign object. By hiding it inside a smooth ball, it thereby relieves irritation. Thus, in the middle of a pearl you can always find the so-called "center of crystallization", in essence, being the germ of a pearl. But it also happens that a pearl is formed around a gas bubble, a drop of liquid, or a piece of tissue of the mollusk itself. Then, during the formation of the pearl, the embryo gradually decomposes, and it may seem that it originated by itself.
The shape of the pearl depends on where the foreign object is placed. If it was not far from the surface of the shell, then its nacreous layer literally grows together with the nacre of the shell, forming the irregular pearl called “blister”. A distinctive feature of the blister is the absence of a nacre layer in the place of its attachment to the sink. But if the object falls into the clam mantle, a pearl of perfectly regular shape grows. Sometimes pearls are formed in the muscles, then it forms an unusual, sometimes - a very bizarre form.
Shellfish with the ability to create pearls are called pearl mussel.They can be both river and sea. At the same time, freshwater pearls are many times cheaper than marine ones. It is much smaller, has not such a regular shape and is far from being so brilliant. But it is much stronger.
Initially, people mined pearls, diving behind pearl shells to a depth of 20 meters and risking being attacked by sharks. However, having learned how a pearl is formed, it was learned to grow it artificially.
Pearls are grown in the following way: by opening the shells of a shell, foreign bodies are placed under the mantle of mollusks, most often pearl beads. Then the sink is placed in a special pond. It takes 3 years to grow a sea pearl, the river grows in 2 years. Pearls grown in this way are called cultured. That he is most often used in the manufacture of jewelry.
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