Since ancient times, pearls have been considered the second most precious stone after a diamond. In nature, there are specimens of the most bizarre shapes and a wide variety of shades. Genuine, natural pearls, obtained from a shell from the bottom of the sea, leave no one indifferent.
Pearls are the first stone that people began to use as jewelry. Pearls are formed as a result of a foreign body entering the shell of a mollusk, which is then enveloped in many layers of mother-of-pearl. It is impossible to find two identical pearls in nature, which makes this stone especially valuable.
The use of pearls began at the dawn of civilization. The extraction of river pearl mussels did not require any specific knowledge and skills. In shallow water, the catchers slowly wandered in the water, probing the bottom. When a mollusk was found, it was simply taken out with hands or feet. In deep and / or cold rivers, shells were fished from rafts. For this, all kinds of tongs, poles, nets, and so on were used. Sea pearls were mined by divers. In Japan they were called "ama". In order to find three or four good pearls, it was required to open the shells of a ton of shellfish. There are up to 600 simple shells for one gem.
There are several signs by which a pearl shell can be recognized. These include the curvature of the valves, small changes or deformations of the valves, traces of trauma, and a rope-like elevation on the shell surface. The pearl is most often located on the ventral edge of the shell, in the most convex side.
Saltwater pearls are valued somewhat higher than freshwater ones. Sea pearl mining is currently carried out in the Red Sea, the Persian Gulf, off the coast of Japan, Bahrain and the island of Sri Lanka. River pearls are mined in Russia, China, Germany, North America. Freshwater pearls account for the largest share of the harvest.
Since the work of divers is extremely tiring, dangerous and often “ungrateful”, at the beginning of the 20th century, people began to artificially grow pearls. For this, the mollusks are placed in comfortable conditions, a piece of mother-of-pearl is introduced into the mantle of the shell and waited until a pearl is formed.