Guest mollusk-pearl
The pearl is nothing like the limestone formations inside the body of a number of bivalve mollusks found in marine and freshwater coasts and are related to anomalies of the mantle of the animal. The chemical composition is a compound of calcium carbonate and organic substance of protein type. Organic — it is a frame of pearls. In the form of education are different. The most common round stones, rarely drop-shaped and pear-shaped. The most rare — unusual shape resembling an ellipse.
Color of pearls depends on the type of mollusk is the pearl oyster, in which it was formed. The color is very diverse: black, white, Golden, bronze, pink, black. Meet blue, green, violet, and lavender stones. Moreover, the hue varies from deep to pale. The hue of monasticism affected the inner mother of pearl layer of the shell, and place attached grit.It accidentally got a grain of sand causes irritation, the mollusk tries to expel a foreign object from its body, enveloping her nacreous layer secretion, gradually increase the new layers. Eventually formed a unique iridescent composition and shimmer pearl. More than freshwater, saltwater pearls are prized. It is believed that the quality of education is affected by the surrounding water temperature and even the health of shellfish, as well as the food he takes.
Pearl is one of the most sought after stones in the jewelry trade. They prefer royals are female. Beauty, originality, exquisite appearance of the jewelry make them the subject of hype beauties of all ages, the popular attribute of the publication. Extraction of natural pearls is many centuries old and is risky. However, seven centuries ago, the ubiquitous Chinese found a way and started getting artificially extracted semi-precious stone. What is a cultured pearl.
Pearls from different coasts
The basic idea is to create conditions close to natural, when the body caught clams of a suitable form is introduced stimulus triggers the secretion of nacre. Most often, the stimulus acts artificially carved from the shell of a freshwater oyster mother of pearl bead or core. The invention is patented and is called the nuclear method of growing.
Cultured pearls are divided into types, its varieties depend on the place of breeding:
Japanese Akoya. Cultivated in the sea of Japan. The largest plantation faux pearl in the world. There are exquisite pearl pink, white pearls, and the stones with silver and greenish tint. The process takes up to four years, diameter of the pearls is 8 mm. Perfect shape — spherical.
Japanese_akoya
Japanese Akoya pearls
The South sea pearls. Grown near the shores of the Indian and Pacific oceans. Most major commercial species. The middle pearls have a size of 13 mm, often reaching 20 mm. This is due to the large amount of oysters to pearls, favourable conditions and technology of cultivation, when the vaccine into the body of the clam is at the age not earlier than 2 years. Cultured pearls from these districts are characterized by delicate pastel shades of silver and Golden mother-of-pearl, thick layer, and the extraordinary matte-satin sheen.
Golden South sea pearls
Pearls Of Tahiti. Cultivated off the coast of French Polynesia. cultivation of rare black pearls. But the range of shades can be wide. Large pearls have reached a diameter of 16, rarely 20 mm.
Pearls Of Cortez. Grown in the warm waters of the Gulf of California. The major difference is the wealth of overtones. Available in purple, lavender, green, Golden shades with a deep layer of mother of pearl, gorgeous rabenou and extraordinary tints.
River, freshwater. The most affordable and versatile type of cultured pearls. A leader in farming this species are pearl farms of China. The unique difference of this method is the opportunity to plant and to “educate” in the body of oysters to 12 pieces pearls. The result of production becomes more than 1.5 tons of pearls annually. The range of hues — from dark-purple to light pink and white.
0962790055-dlya-ukrashenij-zhemchug-rechnoj-oval-2-3-mm-n2201
Necklace made of threads of river pearls
In addition to belonging to the place of cultivation on the types of pearls are classified according to the method of production. For example, cultured Mabe pearl is a pearl, received a blister method. That is, the implant implanted in the tissue of oysters, attach themselves to the walls of the shell. The result is a unique pearlescent surface, which after removal of the filled epoxy resins and is used for inserts in pendants, rings. Other pearls — Keshi — have fantasy in the form of seed, appear as the product of rejection during implantation.Are rare with a thick layer of nacre and a strong natural Shine. Popular seeds Keshi lavender and pistachio shades.
Criteria for the evaluation of cultured pearls:
Shine. One of the main factors. The more shiny the pearl, the better.
Color. Determined under natural light in a visual way, the application of background substrates.
The thickness of the layer of nacre. Usually used method direct measurement with a magnifying glass and scale.
Size. More valuable than those that are larger. Depends on the conditions of cultivation and the type of mollusk.
Form. The typical form is spherical, but there are many varieties. Is determined by rolling on an inclined surface.
The cleanliness of the surface. Visually determine visible defects and inclusions, which include grooves, bumps, uneven luster and prokras.
The selection of pearls. The criterion applies for the selection of specific products with two or more stones. Strict account on the basis of all the factors in the preceding list.