Pearl Pearl is an organic gem, which has been regarded as a rare treasure since ancient times. According to the research of geology and archaeology, there were pearls on the earth 200 million years ago. China is one of the first countries to use pearls in the world. As early as more than 4,000 years ago, it was recorded in Shang Yu Shu Gong that mussels could produce pearls, and there were also records of pearls in The Book of Songs, The Classic of Mountains and Seas, Erya and Zhouyi. Pearls are divided into natural pearls and cultured pearls according to their causes. Natural pearls mainly refer to pearls naturally formed in shellfish and mussels. Traditionally, pearls are divided into three types: seawater pearls, freshwater pearls and artificial pearls. Freshwater pearls refer to pearls produced in rivers. China's natural freshwater pearls are mainly produced in lakes in the south of China, and Zhuji, Zhejiang is a famous pearl town. There are five kinds of pearls: white, red, yellow, black and variegated, and most of them are opaque. In ancient times, people called natural round pearls walking beads. Pearl, agate, crystal and jade are also known as the ancient traditional "Four Treasures of the Study" in China. At present, the pearl culture technology in China is very mature, and the price of pearls is correspondingly popularized. Huang Xiang Jewelry can promote pearl necklaces to female compatriots all over the country, so as to maximize the value of pearls. According to the latest scientific investigation, the earliest pearl on the earth appeared in ancient times about 200 million years ago, and the round and crystal pearl is the crystallization of shellfish life. China is one of the first countries to discover and use pearls in the world. The Postscript to the History of the Sea contains a record of "Cao in Dingnan and Dabei in Zhuji" as a tribute, which may be the evidence that China used pearls 4000 years ago. Lu's Spring and Autumn Annals in the Spring and Autumn Period, Huai Nan Zi by Liu An in the Han Dynasty, Wen Xin Diao Long by Liu Zhou in the Liang Dynasty, Tiangong in the Ming Dynasty and Song Dynasty, and other ancient records about pearls all reflect the ancients' understanding of pearls. Yugong recorded "Huai Yi Ju Zhu" in Shangshu. Er Ya Ba Zhu and Yu are both called "the beauty of the West". Records of pearls in ancient books such as Lisao in Chu Ci and Sang in Shang Mo in Han Yuefu reflect the custom of ancestors wearing pearls. It is written in Compendium of Materia Medica that pearls have the functions of "treating eyes and moistening muscles" and "calming the heart and calming the mind", and the medical classics such as Shennong's Herbal Classic and Haiyao's Herbal Classic all have the medical functions of pearls. [Edit this paragraph] The English name of the original Pearl is Pearl, which evolved from the Latin Pernulo. Its other name, Margaret, comes from ancient Persian Sanskrit, which means "son of the sea". As early as ancient times, when primitive humans were foraging by the sea, they found white pearls with colorful auras and were attracted by their crystal splendor. Since then, pearls have become people's favorite ornaments and have been passed down to this day. Pearl is an ancient organic gem, which is produced in mollusks such as Pinctada and Pinctada. The calcium carbonate-containing mineral (aragonite) beads produced by endocrine function consist of a large number of tiny aragonite crystals. The chemical composition of pearl is: CaCO39 1.6%, H2O and organic matter are 4% and 0.4% respectively. Pearl forming principle: 1. The mantle of the peripheral mussel is stimulated by the invasion of foreign bodies (sand and parasites). The epidermal cells in the stimulated area take foreign bodies as the core and fall into the connective tissue of the mantle. Some trapped epidermal cells divide themselves to form nacre, which secretes nacre and wraps the core layer by layer to form pearls. Pearls with foreign bodies as the core are called "nucleated pearls". 2. After pathological stimulation, a part of the outer skin of the mantle undergoes cell division and separation, and then it is wrapped by organic substances secreted by itself, and gradually falls into the connective tissue of the mantle, forming pearl sacs and pearls. Because there is no foreign body as the core, it is called "seedless pearl". At present, cultured pearls are cut from the mantle of pearl-breeding mussels by artificial methods according to the above principles, and implanted into the connective tissue of the mantle together with the artificial nucleus prepared by mussel shells. The implanted cell fragments proliferate rapidly around the artificial nucleus by the nutrition provided by connective tissue, forming pearl sacs and secreting nacre, thus producing artificial nucleated pearls. Artificial seedless pearls are pearls produced by implanting only small pieces of cells into the mantle, forming pearl sacs through cell proliferation, and secreting mother-of-pearl into the sacs. The main pearl-producing shellfish are Pinctada martensii of Pinctada martensii, or Hyriopsis cumingii and Cremastra plicata of Hyriopsis cumingii. 1. Fritillaria Fritillaria alias: pearl oyster. Warm benthic shellfish have different shell sizes, often the left shell is larger than the right shell, and the length and width of the shell are slightly equal. Ersari (ravitrona) caputerntis (L.)-Mollusca, Claphabranchia, Pseudoclaphabranchia, Pinctada, a warm benthic shellfish with two shells, the left shell is slightly larger than the right shell, and the depression is deeper than the right shell. The length and height of the shell are almost equal, generally about 6 ~ 7 cm, and the maximum can reach more than 10 cm. The preauricular process is large and short, and the posterior auricular process is long. The shell surface is yellow-brown, with black radiation stripes. The growth level is obvious. The scales are dense, fragile and broken, and smooth near the top of the shell. The shell is white or yellowish with pearl luster. The shell edge is thin and yellow-brown, and there are 1 ~ 2 main teeth at the hinge. Ligaments are slender and brown. The muscle scar of the closed shell is large, slightly ear-shaped, almost in the center of the shell. The top of the shell is located at the front end, which is close. Feet are small, and silk thread can grow out from the small hole in front of the right shell. Sand attached to rocks. When mother-of-pearl and mussel grow in water, if tiny sand or hard creatures accidentally break into the mantle inside the shell, the mantle will feel uncomfortable after being stimulated, so the secreted mother-of-pearl will gradually surround the sand or creatures that break in from the outside and become pearls day by day. Pearl culture is also based on this principle. Generally, individuals about 3 years old are selected for nucleus insertion surgery, and sand particles are consciously put in, which makes the mantle feel uncomfortable and secretes a large number of real pearls to wrap these sand particles, thus forming artificial pearls, and even artificially making the input into various shapes. Therefore, cultured pearls are also diverse. It is found in the warm sea with a depth of 1 ~ 10 meter. Larvae inhabit shallow water and gradually move to deep sea when they grow up. Mainly distributed in Hainan Island and Guangdong coastal areas. 2. Freshwater benthic shellfish Dianthus plicata. The shell is approximately triangular. The front is short and low, the coronoid process at the front and rear edges is not obvious, and the rear edge protrudes obliquely upwards ... this is a big crown. Cristaria plicata leach is a kind of freshwater benthic shellfish in the family Mustidae, and there are several ribs on the top of the shell. The shell is very thick, just like an equilateral triangle. The front part is short and low, the coronoid process at the front and rear edges is not obvious, and the Kobuko and the rear edge are inclined upward, extending into a big crown. The back of the shell has a series of longitudinal ribs, which gradually thicken from the top of the shell. The abdominal edge of the trailing edge circle is almost straight. The top of the shell is about 1/6 from the front shell, and there are several ribbed veins on the top of the shell. Adult crowns often leave only remnants, and larvae' shells are generally intact. The shell surface is dark yellow-green to dark brown, and the top of the shell is often eroded and loses its surface color. Strong hinge and strong ligament, located at the base of crown. The left shell and the right shell each have a high back tooth. The front teeth are thin, and there are several longitudinal protrusions and grooves below the rear teeth corresponding to the outside. The front closed shell scar is wedge-shaped, the extended foot scar is round, the front contracted foot scar is small and deep, the rear closed shell scar is large and shallow, the shell scar is wide, and the pearl layer is shiny. Living in the mud bottom of rivers and lakes, moving slowly. It is distributed all over the country, including Jingbo Lake and Songhua River in Heilongjiang Province, Ningguo in Anhui Province, Wujin in Jiangsu Province, Beijing and other places. This mussel can be used to produce real pearls, and shells are the raw materials for making buttons. Note: Most of the substances that make up pearls and shells are calcium carbonate. Calcium carbonate forms calcite, aragonite, etc. Have different crystallization conditions. Pearls are made of aragonite, while shells are prismatic layer made of calcite. Therefore, although they are all calcium carbonate crystals, different substances-pearls and shells-are formed due to different crystal systems. Pearl industry in China (1) in Han Dynasty was divided into South Pearl and North Pearl according to regional characteristics. (2) China's pearl mining reached its peak in Ming Dynasty. During Hongzhi period (1488~ 1505), the annual output of pearls reached 28,000, which were exported to the international market. (3) Due to people's indiscriminate mining, pearls eventually dried up in the late Qing Dynasty. (4) From the Qing Dynasty to the Kuomintang period, the natural resources of pearls were destroyed day by day, and the pearl industry went from bad to worse, almost on the verge of extinction. (5) After the establishment of People's Republic of China (PRC), a pearl farm was established in Hepu Bailong on 1958. (6) Zhuji, Zhejiang established the largest freshwater pearl market in China from 65438 to 0985. (7) At present, the output of freshwater pearls in China accounts for more than 95% of the world's output, and cultured pearls are developing towards high quality. Historical Evolution China is one of the earliest countries to use pearls in the world. As early as more than 4000 years ago, pearls were the treasures of our court. Pearl is listed as an important medicinal material for treating diseases in the famous doctors of Wei and Jin Dynasties, and its efficacy is expounded. In "Japanese Materia Medica", pearls are "reassuring and clear-sighted." "Herbal Yi Yan" said: "Except for children's fever." "Herbal Yan Hui" said: "Calm the mind, calm the mind, soothe the nerves, detoxify, remove evil sores and recover internal decay." More than 2,000 years ago, it was recorded in Liu An's Huai Nan Zi in the Han Dynasty: "The pearl of the bright moon is a disease of snails and mussels, which is also beneficial to me." It shows that China has realized the cause of pearl at this time. /kloc-In the 3rd century, China planted mussels with lead as the core and successfully cultivated nucleated pearls. Ecological environment Pinctada martensii lives in seawater with rich nutrition, abundant plankton and fertile water quality. Generally, they live near the low tide line to a place with a water depth of more than 20m, with a water depth of10m. As a benthic mollusk, mussels generally live in freshwater environments such as rivers, lakes, swamps, streams or paddy fields. [Edit this paragraph] Biological characteristics Pinctada martensii is generally hermaphrodite, but it has degeneration, so sometimes hermaphroditism can be seen. The suitable living temperature of Pinctada martensii is 15 ~ 30℃, and the proportion of seawater in its habitat is required to be high, which is1.0150 ~1.0280. Pinctada martensii, born in the first year, has reproductive ability in the second year. The breeding season is concentrated in May ~ 65438+10 every year. (1) Animals [Edit this paragraph] Other names of pearls are Zhu Zhen, Zhu Zhen, mussel pearl, pearl, and lotus pearl [Edit this paragraph]. They harvest all year round, usually in1February. They dive to the bottom of the sea, take mussels from aquatic plants or stones, and take out pearls from them. Meat is edible. [Edit this paragraph] Wrap it in cloth, put it in tofu brain, cook it for about 3 hours, take it out and wash it, and grind it into very fine powder. First, clean the system (Pharmacopoeia 77). 2. Cut into powder 1. Take clean pearls, add appropriate amount of water for grinding, then add water, stir, pour out the suspension, repeat the above operation several times, remove impurities, combine the mixed solutions, stand, separate and precipitate, and dry to make the most fine powder (Pharmacopoeia 85). 2. Take pearls, wash away dirt, wrap them in cloth, add tofu and water, cook for about 2 hours, take them out, wash them with clear water, mash them, add a little water, grind them into very fine powder, and dry them to get the finished product (Pharmacopoeia 63). 3. Take clean pearl powder, put it in a mortar, add water and grind it fine, then add water, stir, pour out the suspension, dry it and grind it. Or take clean pearls, mash them and grind them into very fine powder (standard). 3. fry 1. Wash the products made of tofu (1), wrap them in cloth bags or gauze, cook them in tofu or soybean milk for 2-3 hours, take them out, wash them, mash them, and fly them into very fine powder with water. 65438+ 0kg for each pearl, 2kg for tofu or 5kg for soybean milk (Ningxia). (2) Take pearls, wrap them in cloth, put them in tofu blocks, steam them for about 3 hours, take them out, wash them, dry them, and grind them into very fine powder (Inner Mongolia). 2. Calcined clean pearls, separated by size, placed in an iron pot, buckled with a bowl, calcined with medium fire until the explosion is complete, taken out, air-cooled, flown in water or ground into extremely fine powder, and dried (Shandong).