Shell pearls are formed because pearls are an ancient organic gem. Mainly produced in mollusks such as pearl shellfish and Pinctada; The calcium carbonate-containing mineral (aragonite) beads produced by endocrine function are composed of a large number of tiny aragonite crystals. According to the research of geology and archaeology, there were pearls on the earth 200 million years ago [1]. The international gem circle also lists pearls as lucky stones for June birthday and commemorative stones for 13 and 30th wedding anniversary. Pearls with magnificent colors and elegant temperament symbolize health, purity, wealth and happiness, and have been loved by people since ancient times.
External cause
The mantle of mussels is stimulated by the invasion of foreign bodies (sand and parasites). The epidermal cells in the stimulation area take foreign bodies as the core and fall into the connective tissue of the mantle. Some of the trapped epidermal cells divide themselves to form nacre, which secretes nacre and the nucleus is wrapped layer by layer to form pearl. What's the name of taking foreign bodies as the core? Nucleated pearls? .
internal cause
After pathological stimulation, a part of the outer skin of the mantle undergoes cell division, and then it is separated, coated with organic substances secreted by itself, and gradually falls into the connective tissue of the mantle, forming pearl sacs, and then forming pearls. Because there is no foreign body as the core, it is called? Seedless pearls? .
According to the above principle, cultured pearls are cut off from the mantle of cultured mussels by artificial methods and implanted into the connective tissue of the mantle together with the artificial nucleus prepared by mussels. Implanted cell fragments proliferate rapidly around the artificial nucleus under 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.
Pearl Culture China is a veritable ancient pearl country in the world, and the records about pearls can be traced back to 2200 BC. According to Shangshu? Yu Gong contains:? Huaiyi Zhu Bin? It shows that the history of pearl picking in China began as early as 4,000 years ago in the Yu Xia era, and the freshwater pearls produced in the Huaihe River basin were also regarded as tributes at that time. There are records about pearls in Zhouyi, The Book of Songs and other ancient books. "Original GeZhiJing? Zhou Wenwang decorated her bun with pearls. Therefore, it is generally believed that pearl decoration in China began in the Eastern Zhou Dynasty. Since Qin and Han Dynasties, pearl decoration has become more and more common. Pearl has become a luxury of court dignitaries, and the emperor has begun to accept pearls. In the Eastern Han Dynasty, Guiyang, the prefect of Guiyang, asked Emperor Shun of Han Dynasty. Offer pearls for flattery? Pearls were also widely used by royal princes in the Western Han Dynasty and became a symbol of dignity.
During the Western Renaissance, famous paintings? The birth of Venus? It vividly depicts the fairy tale of pearl formation: Venus, the goddess, slowly emerges from the sea with a huge shell that is slowly opening, and countless water drops fall on her body, instantly turning into a white pearl, which is vivid and gives people a beautiful feeling.
Throughout history, pearls have always symbolized wealth, happiness, happiness and nobility. In feudal society, dignitaries used pearls to represent status, power, money and aristocratic status, while civilians used pearls to symbolize happiness, peace and auspiciousness.
Fritillaria Fritillaria
Alias: pearl oyster
Warm benthic shellfish have different shell sizes, often the left shell is larger than the right shell, and the shell length is slightly equal to the shell width. The preauricular process is large and short, and the posterior auricular process is long.
Molluscs, Claphabranchia, Pseudoclaphabranchia, Pteristidae, Mollusca.
It is a warm benthic shellfish with two shells, which are not equal. 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.
Cremastra plicata
Freshwater benthic shellfish. 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. There are several rib veins at the top of the shell.
Cremantria plicata of Mytilapia
Freshwater benthic shellfish. 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 weak, and there should be several longitudinal protrusions and grooves below and outside the rear teeth. 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.
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.
Ma Bei Pearl
It is a kind of semi-pearl, also known as Mabei pearl, steamed bread pearl and semi-circular pearl.
Generally, after the cultured pearls are collected, the prefabricated semi-shaped pearl core is inserted into the inner wall of the shell, so that the convex surface faces the mother-of-pearl shell and the plane is close to the mother-of-pearl shell wall. After insertion, feed in water. Over time, the pearl layer wraps the outer pearl core layer by layer, forming a semicircle. When it is collected, it is extracted together with part of the shell wall of mother-of-pearl, and polished into an ornament, so it is huge. Mabibizhu is essentially a kind of regenerated pearl. Before this, each pearl oyster can produce two round pearls first, and then cultivate 3-7 Mabibi pearls. Especially Australian Mabibi beads have high yield, good quality, large particles, excellent luster, pure silvery white and smooth surface. The smallest is 10mm, and the largest is 17mm or more, with various shapes such as round, drop-shaped, oval and heart-shaped. Ma Bizhu jewelry is very popular in the world jewelry market. It is not only the pet of ladies and gentlemen, but also the unique and elegant jewelry created with Ma Bizhu is especially favored by gentlemen.
Shape classification of pearls (1) round beads
Refers to round pearls, which are divided into three types according to roundness, namely round pearls, round pearls and nearly round pearls.
The right ball refers to the ball with the best roundness, which is also commonly known as the walking ball in business. The ratio of the difference between the maximum diameter and the minimum diameter to the average straight diameter is less than 1%. A round pearl refers to a pearl with a very round shape, and the percentage of its diameter difference is between 1%-5%; Near-round pearls refer to pearls that are close to round pearls in morphology, and the percentage of diameter difference is between 5%- 10%.
(2) oval beads
Refers to the oval pearl whose length-diameter ratio is greater than 10%. It can be further divided into short ellipse and long ellipse according to the percentage of long and short diameter difference, and the percentage of long and short diameter difference of short ellipse is10% ~ 20%; The percentage of the diameter difference of the long ellipse is greater than 20%.
⑶ Flat bead
Refers to a plane shape with one or two sides, such as oblate circle, oblate ellipse, pie shape, diamond shape, square, etc. This kind of pearl is most suitable for making pearl beads.
(4) Ma Bizhu
It is a kind of semi-bead, also known as Mabeizhu, steamed bread bead and semi-round bead, also known as Mabeizhu.
5] shaped bead
In addition to round beads, oval beads and marbi beads, there are many pearls with different shapes. Pear-shaped pearls, drop-shaped pearls, rice-shaped pearls, potato-shaped pearls, bean-shaped pearls and other pearls are collectively called shaped pearls in business.
Pharmacological effects of pearl 1 Inhibiting lipofuscin and scavenging free radicals: Mice were injected with pearl powder suspension 200mg/(kg. Day) intra-abdominal cavity? After 25 days, the content of lipofuscin in myocardium and brain tissue decreased obviously, and had no obvious effect on liver tissue. PFC extracted from pearl powder of Hyriopsis cumingii and its separated products were determined by chemiluminescence method. The results show that both of them can inhibit luminescence, and PCM- 1 purified by PFC has strong effect and can inhibit free radical reaction in vivo.
2. Anti-tumor effect: intraperitoneal injection of PFC40mg/(kg. God) on mice? S 180 sarcoma cells were inoculated subcutaneously for 9 days. L05 mice /ml had significant inhibitory effect (P
3. Other effects: Pearl extract has inhibitory effect on isolated rabbit intestine.
Pearls grow in pearl mussels in seawater. There are many essence substances and many dirty things in the growth environment of pearl mussels, but mussels can eliminate the dirty things and form the essence into beads. The ingenuity of nature is that when we apply pearl powder to our face, it also has the effect of removing turbidity.
It is recorded in Compendium of Materia Medica that pearls can dilute freckles and chloasma. Modern medical research has also found that pearls contain a lot of trace elements, which have the functions of antioxidation, enhancing skin activity, clearing away heat and toxic materials, whitening skin, promoting granulation, removing acne, controlling oil and lightening spots. At the same time, using it to clean face also has the effect of cleaning deep skin.
Take the most annoying blackhead as an example. Because pearl powder has a very strong adsorption capacity, dirt deep in pores can be cleaned under the adsorption of pearl powder. In a word, pearl powder is like a strict beautician, and can't tolerate anything that is opposite to beauty.
According to Chinese medicine, pearl powder has the functions of calming the liver and suppressing yang, clearing the liver, improving eyesight, prolonging life, calming the heart and calming the nerves, and beauty beauty. I once read a report that a medical university in China observed 100 elderly people who took pearl powder, and found that pearl powder had a certain effect on relieving insomnia, upset and memory loss. Of course, more important is its beauty effect.
Look at how pearl shells are formed, look at:
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