March 25th, 2009 by admin

In the Ancient China people believed the pearls would help to improve sexual energy, enhance sight, and heal the diseases of the ears. According to the legend, the pearls appear from the early dew which was considered to be the tears of the goodness of love. The pearls could give its bearers the foreseeing gift, save from the risky deals and from the evil eye.

The oysters emit the calcite and the mussels emit the aragonite. On the outside surface there is a zone where the calcareous is being produced in a form of the little scales which then are formed into the nacre. In this way the shell consists from the three layers which grow and develop constantly and simultaneously to the growth of an oyster or a mussel.

When the shell is damaged, the epithelium is capable of re-producing all three layers in the correct order. The valve folds of the shell are connected by a strong muscle which when being relaxed opens the shell in order to obtain the food from the water.

Any univalve or bivalve shellfish is capable to produce a pearl, but the types of the molluscs used in our food rarely have even a smallest pearl. Two types of the shellfish produce particularly many pearls- pearl oysters Pinctada and pearl mussels. Only these two types provide enough pearls to make the search for them a successful business. From the ancient times the Persian Gulf, the shores of the southern Arabian, Manaar bay on the northern-west of the Ceylon were the places for the pearls production. It is still true even nowadays, the major share of the pearls on the markets come for the Persian Gulf.

The Red See used to be a place for the massive pearl production, but nowadays the pearls became a rarity in this area. Australia (North and the North-West) is nowadays rapidly becoming a new very rich zone for the pearls production. Other place rich with the pearls are Mergui Archipelago, South Burma, islands Tahiti, other Pacific islands, New Guinea, Kalimantan, Mexican Gulf, shores of Venezuela, California bay and the Western shore of the South America. Japan also has pearls, but there the artificial pearls manufacturing is more popular.

The Romans used to find the pearls in the rivers of England; one of such pearls from the river Conway is now embedded into British royal jewellery. The pearls from the Irish Mountain Rivers used to be highly valued in Europe. Nowadays only in the rivers of Bavaria and Northern America the pearls are still systematically fished for.

The pearls consist of many minerals which however are not shaped into a single crystal, but are rather a conjunction of many little crystals. Therefore, the pearl can have many different and often quite sophisticated shapes.

The shape of the pearl depends upon its position in shell. When some foreign item gets inside, it will be covered by the nacre and this makes a bubbly pearl. The particles can get inside through the space between the valve and if one specially makes the holes in the valves. Those could be sand, little pieces of the shells or insets.

If a particle gets insider via a hole in a valve, that might lead to the creation of rather a big bubbly pearl. The colours of the pearls found in the nature are mostly white; less often one can find the pearls with the rose, blue or green colouration.

The best pearls in the terms of shape are in the bodies of the shellfish. A particle makes a dent in the mantle tissue. The dent will deepen and will have a spherical shape. The annual rate of the pearl forming is 2,30 mm in the first year and after that 0,38 each year and is mostly constant over the years. The pearl might not have a round form if the particle was oddly shaped or if the dent happened to close to the mantle and was also constrained by the outside pressure.

The pearls from the Persian Gulf are usually called Eastern pearls. There are different categories of pearls based-round, baroque, bubbly, seed, drop. The round pearls are mostly valued. The pearls of the especially big size are often called paragon pearls.

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