Written article/Chen Xumiao (Marine Biological Classification and System Evolution Laboratory of the Institute of Marine Research in the Chinese Academy of Sciences)
This article is selected from “Knowledge is Power” magazine
Crystal and elegant pearls are special gems given to human beings generously to human beings. They can be exquisite and magnificent without carving. Since ancient times, they have been treasures in jewelry. There are many types of pearls, different shapes, and gorgeous colors. They are often used in various decorations, skin care products and nutrients in life.
▲ Beautiful accessories made of pearls
How is the mysterious gemstone breeding of these shellfish formed? What is the difference between different types of pearls? Where does their gorgeous color come from? Today, let’s explore the mystery of Pearl together!
Ancient and modern rare treasures
Pearl is a crystal formed by the shells secreted by pearls. The main ingredients are calcium carbonate and various amino acids.
People have a long history of using pearls. In ancient Chinese mythology, pearls were rare magic weapons that wicked evil spirits and defeated the enemy. According to records, in the era of the Yellow Emperor in about 4000 BC, pearls produced by Chinese black mussels were listed as tributes; and it is said that it is said that About 2000 years ago, the Egyptians also mixed with pearl powder in milk and rubbing their bodies. The origin of Pearl itself was earlier. It was found that pearl fossils were not new in geological investigations. At present, the oldest pearl fossils have been unearthed in Hungary, about 200 million years ago.
As a valuable organic gem, pearls have a special luster and shape, exquisitely elegant and dazzling, and are known as the “gem queen”.
Regardless of regional and cultural differences, pearls are deeply loved by women with different skin colors. In recent years, with the leadership of public figures, pearls have once again become a new popular fashion.
▲ Black pearls
Natural products of biochemization
Pearls come from shellfish, and shellfish that can bred pearls are mainly belonged to the double shell outline under the animal animal animal door.
Some of the double shells live in fresh water, and some live in seawater, so that there is a difference between freshwater pearls and sea water pearls. Although there are many types of double shells, there are only dozens of shellfish that can bred pearls, and pearls that can produce gem -level pearls are even more rare.
The shells of the double shell are composed of calcium carbonate crystals. These substances are derived from the meat film of the shellcut software, that is, the secretion of the epithelial cells in the coat. Under normal circumstances, these secretions will accumulate very regularly and form the shell, so that the shells of shellfish will continue to grow. In accident, the small sand or biological larvae fall into the shell coat and the inside of the shell. Once these foreign particles cannot be quickly discharged from the body, they will constantly intercept the secretions of epithelial cells; The secretion gradually precipitated and forms a crystal that is wrapped in small particles, and a bright pearl was formed after a period of time. general speaking,
The formation of pearls is a natural process of biomedicization. The longer the time, the thicker the pearl layer growing.
▲ Mother of Pearl -Pearl Mother Best
The mysterious structure is bright color
The ingredients and structures of pearls are consistent with the female shellfish forming them. Therefore, different shellfish will form a completely different pearl, which determines the brightness of the surface of the pearl.
The pearls formed by the pearl shells from the ocean and freshwater growth are composed of a layer of concentric sheet. These thin slices are consistent with the structure of calcium carbonate minerals — the structure of the grammar. Higher. Pearls will also be found in some oysters and some Jiang Yao, but the interior of this type of pearl is radial columnar structure, which is consistent with calcium carbonate minerals — square lipstick, and their surface light is much inferior.
The gloss of the pearl is soft and beautiful. It is the so -called “pearl and treasure”. The quality of the good quality pearl is shiny like mirror, strong luster, and pleasing to the eye.
Whether it is seawater pearl or freshwater pearl, the more the lithoscope content, the more consistent the form of the structure of the stone tablets.
Proper later processing, such as special polishing technology, can play a role in icing on the cake on the improvement of pearl luster.
A large number of studies have shown,
Different colors of pearls are rich in trace elements
: Orange pearl is rich in iron, purple pearls are rich in magnesium and manganese, pink pearl is rich in ravioli, nickel, chromium. In seawater pearls, the content of metal trace elements is often negatively related to the quality of pearls. For example, when the content of magnesium, iron, manganese, zinc and other elements is too high, the density of the stone structure will decrease, resulting in the dim lus of the pearl.
In addition to metal trace elements, organic matter such as pyrine and polymien compounds is also the main color factors of pearls.
For example, shellfish is deposited in the body by carotene (a type of polylamic compound) obtained by taking algae, which determines the color of the pearl.
▲ Ball beads and alien beads with different colors
A variety of large families
There are more classifications of pearls,
Pearl trading is usually classified according to the origin, shape, diameter and cause of pearls (natural, breeding).
According to the place of pearl origin, it can be divided
It is Nanyang Pearl, Daxi Pearl, Agu House Pearl, China Freshwater Pearl, etc.,
Divide according to shape
It is ballpoints, oval beads, Marbicades (such as steamed buns), alien beads (such as pear -shaped beads, waist drum beads, egg -shaped beads, rice -shaped beads), flat beads, etc.
Pearl’s body color
There are mainly white, red, yellow, black, and others. Generally, except for the lack of black systems in freshwater pearls, other colors are available, and even special colors, such as purple, brown, brown, copper, blue, and green; Many times, the types and origin of the pearl mother can be preliminarily judged by the pearl color: the pearls of the Agu House are mostly white, and some are luster such as pink, gold, blue, purple. Hepu Pearl), breeding in Mie Prefecture, Honshu Island, Japan; black pearls in Daxi, some of which are gray, blue, purple, green and other luster. It is called “Black Butterfly Bed”), which is rich in Daxi Island in French Polynesia; Nanyang Pearl is mainly white, as well as champagne, gold, and silver. Pearl Mu Bian (also known as “White Butterfly”), produced in Southeast Asia.
▲ Daxi Black Pearl on the Black Bead Mother
In addition to the body color, the color of the pearls also has the same color
(Refers to the rainbow color floating on the pearl body color)
(When the light waves reflex or the interference effect is caused by the interference from the film or due to the diffraction effect, the color effects are seen when some colors are strengthened), they together form the rich color of pearls. Common pearls are silver, pink, rose, and green, while blue, yellow and cyan are rare. But not all pearls have fainting. Generally, the fainting of white pearls is mostly obvious and strong, and the yellow pearls are weak. Special purple, bronze, and silver pearls have strong faint. It can be described as glorious.
▲ The strong gloss golden pearl
The artificial breeding pearl of ingenuity
The probability of natural pearls is very small, and it is very difficult to catch, so the output of natural pearls is very low. So, hard -working and intelligent people try
Through artificial intervention and actively invading foreign bodies into pearl mother shellfish, pearls are obtained.
In this process, the formation of pearl quality is still completed by the natural secretion of pearl mother and shellfish, and there is no manual intervention. Therefore, breeding pearls are also natural organic gems. The history of Chinese pearl breeding can be traced back to the Song Dynasty. It is said that during this period, the pearl nucleus of the shape of the Buddha statue was inserted into the pearl mother shell to obtain the Buddha statue.
Natural pearls have a colorful luster, so is the breeding pearl? In order to meet people’s needs for pearls,
Color pearl breeding technology came into being, that is, to add metal components to the pearl nucleus, or use corals to make pearl nucleus to form color pearls.
For example: steamed trice chromium dioxide, titanium oxide or nitride on the pearl nucleus, can get strong gloss green pearls, golden yellow pearls and black pearls; When nuclear, you can get pale purple -red pearls and cherry red pearls. The wonderful craftsmanship of such a clever work greatly enriches the diversity of pearls, and also increases the value of artificial breeding pearls.
At present, China’s freshwater pearl farming has the advantages of short cycles and large output, and its output ranks first in the world. In recent years, the pearls produced by the triangular sails have been large and round, with strong luster and rich colors.
The natural brilliant gem such as pearls is a miracle of nature; the long river of history, people not only learn how to use pearls as noble jewelry, skin care products and nourishing products, but also by scientific development. The wings have a profound understanding of the structure and formation mechanism of pearls.
The use of this knowledge of wisdom not only creates an excellent cause of artificially breeding pearls, but also applies the pearl mineralization mechanism to the preparation of bionic materials to develop high -performance composite materials. Its practical significance far exceeds the pearl breeding itself Essence