Cultivation method of pearls
(A) Mytilus artificial culture technology
At present, Hyriopsis cumingii is the most important shellfish for cultivating pale pearls in China.
1. For most mussel farmers, pearl mussels are generally not cultivated. Judging from the development of industrialization, there is no need for professional companies to complete the three production links of "artificial seedling raising-operation mussel culture-pearl culture operation". Generally, farmers only engage in pearl mussel breeding. Judging from the current production situation, most people buy young mussels, raise and manage them themselves, and then hire people to manage them. So briefly introduce the breeding process of mussels.
When the breeding season of mussels comes, female mussels pregnant with eggs are generally selected directly from mature pearl mussels, and when their fertilized eggs develop into hookworm larvae, they are collected (delivered) with Pelteobagrus fulvidraco in time.
20-30 small fish parasitized with hookworm larvae can be placed in each square meter of running water seedling pond. The nursery pond should master a certain amount of water flow, but the flow should not be too fast. Feed the fry every day to make them grow normally. When the water temperature is above 30℃, hookworm larvae mature in 4-7 days, and it takes 7-9 days at 25-30℃. The hookworm larvae parasitic on fish begin to live freely after shedding, which is called juvenile mussel. This process is called seedling removal. Young shellfish (65438±0-2mm) were cultured in shallow ponds in nursery until they grew to about 65438±0cm. The production process is as follows: pregnant mother mussels → hooked larvae → Pelteobagrus fulvidraco seedlings → young shellfish cultivation → young shellfish.
2. There are many ways to cultivate young mussels to operate mussels, but mussel farmers in Zhejiang widely use the method of cultivating mussels in small cages with large water surface in production, and the effect is quite obvious. The young mussel of 1 cm was directly cultivated into an operation mussel of about 8 cm, and the time was shortened to about 3 months. This reform made it possible to raise seedlings and pearls by surgery that year.
The general specification of this Xiao Mu cage is (40-45) cm× (40-60) cm× 10 cm, and it is made of Chinese fir (or bamboo) strips, and the specification of Chinese fir strips is generally (1.5-2) cm× (3-4) cm. After the wooden frame is nailed, it is closed with a 2 cm net, leaving a seam on the upper part. The bottom of the cage is padded with plastic film and placed with fertilizer mud. It is appropriate to put about 0/50-200 young shellfish in each net, so it is expected that more than 60% young shellfish will be cultivated into operational mussels in the autumn of that year.
The aquaculture water area should be above 10 mu, and the water level should be at 1.5-2.5 meters. 3-5 days before the young shellfish are put into the box, base fertilizer should be applied according to the water environment (xintang or laotang) and the fish stocking situation (50-200 flowers and silver carp in a certain proportion/mu) to improve the water quality. Make the water light brown or yellow-green, and the transparency is 30-40cm. The water quality of young mussels should not be too fat before 3 cm, otherwise a slightly higher concentration of ammonia and nitrite ions will inhibit their growth.
In the process of culture, topdressing should be done in time according to the change of transparency and water color, generally once every 10- 15 days, and wet pig manure 150-250 kg/mu should be used each time. Fertilizer must be fully fermented and decomposed. It is best not to use chicken and duck droppings. It is recommended to use professional compound fertilizer (the dosage can be according to the instructions), which is safe and efficient.
When the young mussels grow to 3-5 cm, the amount of fertilizer can be appropriately increased to improve water fertility (transparency 30 cm). In addition, quicklime should be applied every 10- 15 days (10 kg/mu). During the whole cultivation period, topdressing should be done in time when the water becomes weak and the transparency increases. But blue-green algae must not flourish, otherwise the transparency will drop below 25 cm.
If scientific management can be carried out according to the requirements, 60% of the young shellfish can reach the surgical specifications in less than 3 months.
(2) Operation technology of freshwater seedless pearls
Transplanting epithelial tissue of shellfish mantle into cultured pearls has always been a basic surgical technique for artificial pearl cultivation. After years of efforts, we have scientifically combined tear film technology with systematic disinfection technology to form a set of new surgical operation techniques, processes and quality management measures. The training of operators and the practice of aquaculture production show that the technology and its management measures not only greatly improve the high-quality pearl rate of "big, bright, round and bright", but also the survival rate of pearl mussels after operation is over 95%, and can effectively prevent the occurrence of mussel diseases.
Identification skills of pearls
(a) the color, size, shape and luster of the beads. They are all identical, that is, artificial pearls. Because real pearls can't be consistent anyway.
The luster of real pearls is like a rainbow, colorful and very beautiful. Fake pearls are dull and have no colorful rainbow tones because of the coating on their surfaces.
③ Real pearls have good transparency, while fake pearls have poor transparency.
④ Real pearls have a smooth and cool feeling through hand feel, while fake pearls are often warm and greasy.
⑤ With a magnifying glass of 10 times, the growth texture can be seen on the surface of real pearls, but there is no growth texture on fake pearls, only the coating can be seen.
The output of freshwater pearls in China ranks first in the world, but the quality is not ideal. At present, China cultivates nearly10 billion young shellfish every year, and the output of pearl mussels can reach 500-800 million. The annual output of commercial pearl mussels and pearls would be more than twice as high if it were not for the massive deaths caused by mussel disease. Therefore, it is urgent to improve the quality of pearls and limit the output.
Diversity of Pearl Culture
He Nanhai pearl
Nanyang pearls refer to natural or cultured seawater pearls produced in countries along the South Pacific. Major pearl producers include Australia, India, Japan, Indonesia, Philippines, Myanmar and Thailand.
Nanhai mingzhu
Nanhai mingzhu
China Nanhai pearl culture.
China Nanhai mariculture pearls entered the international market on a large scale in 1980s, and their output was close to that of Japanese mariculture pearls. China mariculture pearls mainly come from Hepu and Beihai in Guangxi, Leizhou Peninsula in Guangdong and Sanya in Hainan.
Okaya pearl
Akoya pearls are produced in the southern coastal areas of Japan. Mother-of-pearl, known as Akoya, is round and shiny, mostly pink and silvery white, with a general diameter of 6-9 mm. ..
Okaya Pearl is a pearl specially produced by Japanese pearl plantation. The first batch of cultured pearls came into being in the 1920s, and the refraction of white and rose color made pearls present beautiful appearance. Okaya pearls are high quality pearls. You will find them perfectly matched with 18K gold as jewelry. You will also find that this series of pearls are almost flawless and have strong and beautiful luster.
fresh water pearl
Most freshwater pearls come from China, accounting for 80% of the world's output. Every year, China hosts the China (International) Pearl Festival. The mother-of-pearl of freshwater pearl is Pinctada martensii hybrid or mussel, and the roundness and luster of freshwater pearl are the main factors affecting its price.
Freshwater pearls look like Okaya pearls, but the price is only 1/5 of Okaya pearls. What needs to be weighed is that freshwater pearls are generally small and have poor symmetry, and the matching effect is not so good when strung into chains. Sure, but after weighing the price, freshwater pearls are also a perfect gift.
Tahiti black pearl
Tahiti Black Pearl (also known as Tahiti Black Pearl) is produced in coral atolls of French Polynesia in the South Pacific. Mother-of-pearl is a black butterfly shell that secretes black nacre. The beauty of black pearl lies in its colorful colors on the black tone of the sky, and the most appreciated colors are peacock, deep purple, navy and other rainbow colors. Her strong metallic luster changes with the rotation of the pearl, which is far beyond the comparison of other color-changing pearls. Generally, the diameter of black pearls is 8 to 16mm. From round to pear-shaped or even banded.
Tahiti black pearl gives people a vivid style.
This kind of pearl is traditionally called black pearl, but their color series consists of metallic silver-the color of pencil lead. In this series of colors, they are refracted by light, accompanied by overtones of different colors, such as green, deep purple or sea blue.