Cultured pearls are ... Freshwater and marine cultured pearls
Why does a pearl form in the shell? For example, the ancient Greeks were absolutely sure that these pearlescent stones are the frozen tears of nymphs. In this they were practically right. Only in the role of nymphs is an amazing genus of mollusks. When a foreign body gets into their shells, for example, a grain of sand, the pearl woman perceives it as a trauma, starting to "cry" with her mother-of-pearl tears, thereby enveloping them with this alien object. That's how pearls are born.
Natural pearls belong to the category of the mostrare precious stones, therefore, its value is appropriate. Such individual stones are mainly sold at auctions, and are purchased by collectors.
To date, most of the minerals sold in stores are cultivated.
Description
Cultured pearls are a mineral grownman in conditions similar to natural, on special farms. There, behind the seashells, they take care and follow. To date, 99% of the stones in the jewelry market of the world are cultured pearls. Its price is $ 2000-5000 depending on whether it is freshwater or marine. It should be emphasized that this is also a natural mineral, since it is grown in oyster pearl mushrooms under natural conditions, but only with the help of a person and under control. So, the breeder places the stimulus in the form of a pearl ball ("core") in the body of an oyster, and then the process of pearl formation proceeds in the same way as in the case of the appearance of natural stone.
The difference between cultured and artificial pearls
Once again, cultured pearls arenatural mineral. It is a mistake to consider it artificial. The cultivation process is very thin and complex, it takes an average of 5 years. People who grow it do not have the ability to influence in any way the result and the process of growing the pearl, they do not know what the result of their labors will look like, besides, they can not be sure that its clam will not be rejected before the due time. Not all grown minerals meet the quality standards, which means that in this business there is a rather high percentage of rejects. And the result depends mainly only on nature.
Methods of growing pearls
There are two main ways to grow it.
The nuclear-free. This is an inexpensive method, which is most widely used in the cultivation of freshwater pearls.
Nuclear. In this case, a seed (nucleus) is placed in the sink. This method is used to cultivate sea pearls.
Nuclear method
So, how exactly does this happen? Initially there is a pearl donor. Basically, this is a young oyster with a good mantle (as the mother-of-pearl is called). Also pay attention to a well-developed gonad (the reproductive gland that secretes mother of pearl), which is a clam. Pearls are formed in it as follows. The shell with the pearl is opened with pliers, after which a real surgical operation is performed: a small incision is made with special tools in a very soft tissue, into which a graft is inserted - a piece of the donor's mantle. Around him put a small ball, extracted from a freshwater bivalve mollusk. Then the pearl girl goes back to the lagoon, and there she spends two more years in peace.
It should be emphasized that this is the most dangerous period: it can throw a nucleus or die - the probability of this is high. In case everything goes smoothly, a few years later pearls are formed. Here from the visual advantages - the ideal surface of the stone, as the mother of pearl grows a thin layer on an artificial smooth ball. On such pearls the real thickness of mother-of-pearl 0.2-1 mm. In this case, the 10-millimeter mineral grows in a year. Such natural pearls can be called with stretch. When you take it in hand, it immediately heats up, like a piece of plastic - a person and inexperienced instantly distinguish a real, cold and heavy stone from his easily warming weightless imitator.
The non-nuclear method
Advantages of this method of cultivation is thatwith prolonged growth and a fairly small core, the cultivated mineral is not inferior in anything, and often exceeds the natural stone in color and size. At the moment, almost all freshwater cultured pearls, whose size is no more than 8-9 mm, is grown according to this technology. Here as a kernel a tiny grain of pearl is used, which is taken from the shell itself.
Also grown minerals are freshwater and marine, which depends on the pearl's habitat.
Freshwater pearls
It grows in fresh river or lake water, inincluding on the old Chinese rice fields. The fields are completely flooded with water, in this place there is a comfortable microclimate for mollusks, where they multiply rapidly, and also bear pearls. Farmers keep an eye on the temperature of the water, its pH and composition. During the ripening, the pearl of the mollusk needs to be turned from time to time so that the stone does not turn out to be "one-sided". In other words, round pearls get very hard work, including in farm conditions. Freshwater cultured pearls are a very popular mineral due to the variety of size, color and shape. Its average size is 4-6 mm. Very rare size of these pearls is about 10 mm, therefore, for such pearls the price rises sharply!
The most common sink is "Hyriopsisschlegeli », originating from the family Unionide. In it, the outer sides are mostly brown, while the inner sides are white and smooth. Freshwater pearls have no nucleus. The exception is those minerals, the size of which is more than 10 mm. After 1.5 years the size of the stone reaches 3 mm, after another 3 years - 7 mm. They will become 7 mm in diameter after 4 years. Therefore, pearls 10 mm or more grow about 7 years !!!
There are the following shades of freshwater mineral: cream, white, champagne, brown, light purple, lilac and pink pearls.
Forms can be from drop-shaped, ovate, oval to potato-shaped. Very large, completely round pearls are very rare.
Sea pearls cultivated
It is a mineral that is grown on the sameFarms, but only located in the open sea. It is more valuable than freshwater. From one shell, usually no more than one, sometimes three pearls are extracted. Basically, they have the right shape, beautiful shine. Why is there more price for such pearls? Sea salt water gives it a more even color and a special shade, rather than fresh, so its cost is higher.
Sea pearls grow faster than river pearls. At the same time, the lifespan of such a pearl shell is 8-10 years. It is necessary to understand that in the sea it is very difficult to save mollusks from sudden changes in water temperature and storms. So, when the temperature changes by 2˚, the mollusc organism immediately begins to produce an acid that corrodes the pearl, or rather its upper layer, and it loses its shine and becomes turbid. Consequently, pearl farmers for 1 day often lose the result of labor for several years. Due to this, to reduce the time of maturation of the mineral today, many marine farms use a seed nucleus.
Cultured pearls of Akoya
This natural sea pearl is grown onsouth of Japan. At the end of autumn, his best harvest of pearls is collected. Then the mineral gains maximum brilliance. This stone in diameter reaches 9 mm and is very expensive. Its price starts to grow with each new millimeter in case its diameter is more than 8 mm. Most of it is cultivated in Japan, although now China has also started exporting it.
The mineral is grown in 2-folding mollusks, which belong to the genus Pinctada, whose name in Japanese sounds like Akoya-kai. Actually, hence the name of this stone appeared.
These mollusks reach 7-8 cm, while their sizepearls - 6-8 mm. In this case, minerals of larger sizes are much less common. Most of the pearls are collected on the islands of Kyushu and Honshu. The oldest and most famous place of cultivation is the bay of Ago.
Usually the cultivation process takes 1.5-4 g.
Akoya pearls with its quality characteristics are called Hanadama. It belongs to the class AA and AAA. The minerals of class B and A are about 30-40% of the total volume.
The main colors of the stone: light cream, pearl white and pink pearls. Periodically there are minerals of silvery-greenish and silvery shades.
The shape of the pearls is different, and the most ideal is the spherical shape.
Pearls of the South Seas
Roads, rare, while the market takes an eliteniche. In Indonesia and Australia, golden and white pearls are produced. Despite the fact that the cultivation process is almost the same as that of Akoya, these stones are much larger: thus, the mineral size reaches 20 mm.
This is a variety of pearls grown with the help of the mollusc Pinctada maxima. At the moment, it is grown near the coasts of the Indian and Pacific Oceans, in the Philippines, Australia, Myanmar and Indonesia.
The bulk of the harvest is 9-20 mm. This size of pearls is provided by various factors:
- Molluscs Pinctada maxima are located along the coasts between South China and Australia. Excess plankton and pure warm water allows pearls to grow faster, and also speeds up the metabolism inside oysters.
- The size of Pinctada maxima in adulthood can reach 30 cm, which makes it possible to implant a much larger nucleus into the gonads than Akoya.
- In the pincers of Pinctada maxima place the nucleus in itsage 1 year, and a couple more years is required in order to grow a mineral. A long cultivation period makes it possible to obtain an elite variety of this large size.
Such stones are especially large in size,warm shades of color and satin matte shine. The farms mainly use 2 kinds of Pinctada maxima: gold-lipped and silver-lipped, in other words, pearls with gold and silver mother-of-pearl, which determines the color of the pearl.
A unique property of this mineral is a surprisingly thick layer of mother-of-pearl - 2-6 mm (the thickness of pearls Akoya is 0.35-1.2 mm).
In the world market also to these stones sometimesthe black pearl is considered, sometimes the pearls of Cortes. But this is absolutely not true. Although according to the classification of CIBJO (International Jewelery Confederation), the concept of "South Sea Pearls" can be attributed only to stones that were grown in Pinctada maxima.
Also in the Australian mineral, the density and structure of the pearlescent shell is much better than that of the Japanese.
Black Pearl
Each such pearl is an amazingthe product of nature, especially considering that none of them in form is repeated. Such a mineral is perfection itself. At the same time he does not need special treatment, he does not need to attach any other form. Each - a pear-shaped, round, "button" - a mineral is incredibly valuable, since it does not require chemical treatment, since the pearls are already sufficiently smooth, dry and clean from the oyster. But not every black stone that can be seen in jewelry shops is actually black. Sometimes the masters paint specifically white minerals to create a special effect. We must understand that this is still a fake, albeit of a very high quality.
Such a high-grade mineral appears in Tahiti. It is distinguished by the ability to pour into the sun, in addition, an interesting "metallic" coloring, which is not characteristic of some other sorts of pearls. There is an opinion that it is often "black", hence its name appeared, but it is actually gray with various shades of it. Also there are stones of this sort with the coloring, atypical for them: blue, aubergine, green, olive, blue and red.
The most expensive type of Tahitian pearl
It includes cobalt blue andiridescent blue color. In a necklace, each pearl should have a rounded shape, while being at least 12 mm in diameter and, of course, ideally suited to its neighbors in color. Such an ornament is worth a fortune, since it is collected for years, since not every master will be lucky to create such a miracle. Nature creates too few such ideal black minerals. Sometimes two similar balls and earrings are not enough.
It must be understood that black pearls always remainon the first roles. His personality makes the master in his decision to build on the magical, hot, swarthy mother-of-pearl shine. Of course, the products from it are always quite extravagant. They can make a woman unique, bright, memorable. Of course, for every girl, black pearls are a real witch drink, a search for oneself, constant renewal, eternal exploration of the depths of one's own personality, and the discovery of an uninhabited mysterious island in the ocean of the soul.
