Jade also belongs to nephrite in mineralogy, which is a hydrated calcium magnesium silicate. Jadeite has a hardness of 5-6, a density of 2.9-3. 1g per cubic centimeter, serrated fracture, oily luster, translucent to opaque. Jade has many colors, including white, blue, green, black, gray, yellow and red. White and delicate jade is called suet jade, which is the most precious variety of jade. In addition, according to the color of jade, the types of jade are white jade, topaz (topaz), sapphire, jasper and jet.
Jade occupies an important position in Chinese jewelry culture. Guanzi said: "A gentleman is better than jade" and personified jade. In modern life, jade is still loved by people, especially women.
Distinguish the quality of jade according to its color, quality and quality. Whether it is white jade, topaz, sapphire or jasper, its jade color must be bright, and the best is not evil or gray. As far as jade and jade are concerned, it is required to be delicate and white, pure and free from impurities. No matter what color of Baoyu is, the finer the quality, the better, and the finer the moisture. Jade jewelry is suitable for people of all personalities and ages. Whether it is a beautiful young girl or a graceful young woman, wearing a sparkling diamond necklace with pure and shiny Baoyu earrings or bracelets will look radiant.
Identification of jade is mainly to prevent nitrate from acting as white jade. It can be identified from the aspects of color, jade, fracture, impurity, specific gravity and sound.
1. color: the white of white jade is often slightly blue, and few people are extremely white and pure white, while nitrate is even white and pure white. After the light is on, nitrate still has a slight orange light.
2. Jade: One of the characteristics of jade is that it is moist and even, like cream. Although the feeling of nitrate is bright and naked, it feels like a thief's light flashing in the bright and moist.
3. Fracture: This is an obvious feature. The fracture of white jade is stony, dull, serrated or serrated, while the fracture of nitrate is material, bright and shiny, and shell-shaped. Although jewelry appraisal can't be destructive, it can be observed through some accidental bumps, unpolished grinding surfaces and corners.
4. Impurities: There are no bubbles in jadeite, but there are bubbles in nitrate. Sometimes it is difficult to be observed because of its translucent color, and sometimes it is rare because of its good quality. But as an appraisal, you can't stop without finding evidence. Sometimes we can check from the surface. If there is trachoma, that is, there are bubbles on the surface, it can also be proved to be nitrate, because white jade does not have this characteristic, and the bubbles inside can also be checked under strong light.
5. Specific gravity: the specific gravity of jadeite is between 2.9-3. 1, and nitrate is about 2.5, which is lighter than nitrate.
6. Voice: The voice of jade is dignified, and the voice of nitrate is crisp. In some cases, it can be identified by the sound difference between jade and nitrate through a gentle impact.
Defendant: Wu Tiantian-University1Grade 6 5-20 20:3 1
One is to look at the color of jade. The second is the sensory quality improved by hands.
Respondent: zqx 2742- trainee magician level 2 5-20 20:32
Look under the light, the color is bright or not, knock to see if it is a stone, and the lines will change after wearing it for a long time!
Responder: Sun Hua-Magic Apprentice Level 1 5-20 20:33
Identification of processed jade
There are three kinds of processed jade: bleached jade, dyed jade and electro-colored jade.
The jewelry industry divides jadeite into three grades: A, B and C. Grade A is the original jadeite stone that has not been bleached, faded and dyed. Grade b is bleached jadeite; Grade C is jadeite that has been dyed or electrochromatically treated. Grade b and grade c belong to processed jade.
(1) bleached jade (grade b jade). It is to remove the variegated colors (such as grayish yellow and grayish black) in jadeite with strong acid to make the main color more vivid, such as "jadeite with white background". Due to acid treatment, its internal structure was greatly destroyed, and its texture became worse and more brittle.
(2) Dyed jade (Grade C jade). Colorless jadeite is indirectly heated. After the pores in jadeite are enlarged, it is put into dye solution for coloring. It must be heated and dyed repeatedly for more than ten times to obtain the effect of colored jade. * * * The jade material used must be hard, and there will be no cracks due to the cold and hot process.
(3) Electro-colored jade (Grade C jade). Inferior jade is plated with a layer of color appearance through electroplating process, which must be carefully observed to distinguish it. If there are some small green cracks with blue on the jade, it means electrochromic jade. Because electroplating will leave cracks, which are called "spider claws" and can be observed with a magnifying glass.
There are generally five identification methods for processing jadeite.
(1) Observe with a magnifying glass. Under the magnifying glass of 10 times, the chemically etched jade will show spider-like texture; If dyed, its color will appear vain and unnatural, and the pigment will be concentrated in cracks or pores invisible to the naked eye.
(2) Observe with a color filter. Natural jadeite will appear grayish green under the color filter, and the darker the color, the darker the gray. If you dye jade, the color filter will filter out the artificial green of jade, and what you see under the mirror is a reddish brown. Bleached jadeite has not been dyed, so its reaction will be the same as that of "A" grade goods containing natural pigments.
(3) Check with spectrum analyzer. The treated jade after chemical treatment and dyeing of high-quality jade will get different spectral patterns under the spectrometer because of the different material structure and composition. By comparing the spectrum of the known A-grade jade with the spectrum of the detected object, the counterfeit will be revealed.
(4) infrared photometer inspection. Its principle is similar to that of spectral analyzer, which can detect whether there are colloidal substances in jade to fill holes, so as to prove whether jade has been bleached or dyed.
(5) Relative density (specific gravity) test. The internal structure of the treated jade is different from the original jade, and its density is small. After precise detection and comparison, it can be identified whether it is original jade or processed jade.
China is a country that loves jade, and it is also the earliest country to exploit and utilize jade in the world. People regard jade as a symbol of beauty and nobility. What is jade? Jade is a beautiful and lovely stone. Exquisite structure, can be used for carving jewelry or handicrafts. It's rare, and it's a little hard to wear.
China is the main producing area of jade in the world, with more than 50 kinds of/kloc-0, but only 20 kinds are rich in reserves and output. At present, only Hetian jade, xiuyan jade and dushan jade occupy an important position in the international gem market.
The main jadeites in the world belong to seven categories: mineral rock type (1) and pyroxene (jadeite): Burmese jadeite, etc. (2) amphibole (nephrite): Hetian jade in Xinjiang, etc. (3) plagioclase: dushan jade, Henan, etc. (4) Ophiopogon japonicus: xiuyan jade, Liaoning; (5) Quartzite: Henan Miyu and Dongling Stone; (6) Dolomite: Xinjiang beeswax topaz; (7) Turquoise: Hubei turquoise, etc.
At present, the most popular high-quality jadeite varieties in the world are jadeite from Myanmar, Opal from Australia and nephrite from China. In addition, turquoise, lapis lazuli, rhodochrosite, andradite, chrysotile and hibiscus are all popular jade varieties.
How to identify the authenticity of jadeite jade
The first thing is to know the difference between jade and stone. Stone is most easily confused with jade. The stone is artificially smelted, with loose structure and even green. Although it is deliberately uneven, it is unnatural. The broken part of the stone is bright, easy to wear and lose its light. The stones are light, and some have bubbles. Emerald is a natural mineral with compact structure and uneven green color, but it is natural, green and bubble-free. The broken part of jadeite is ballast, which has great hardness and weight.
The second is to know how to identify colored jadeite. Put the colored jadeite in nitric acid or sulfuric acid, and the green will fade after several hours. Put the colored jadeite on the iron at 70~80℃, and the green will fade after a few hours. These two characteristics can be used to distinguish colored jadeite from natural jadeite.
Third, we should know the difference between jade and green natural minerals: the green of natural minerals that are easily confused with jade is not as bright as jade, and their characteristics are different, such as jasper, most of which have black spots and the black spots are triangular. Australian stone, blue with blue head, impure color. Green agate, green flashing blue, uniform color, but turbid. Dongling stone, green flashing blue, flashing gray, with a small white star shining on the surface.
In addition, spectroscope is a key tool to distinguish dyed jadeite from natural green jadeite.
The identification of jade ornaments should be based on hardness, transparency, color, luster and spots. Real jade is very hard and wear-resistant, crystal clear, pure and beautiful in color and sparkling. If you can see cracks, fibrous cotton threads or dark wounds in jade, it is inferior jade. All fake jade has wrinkles on the surface and bubbles inside, which is light in weight and low in hardness, and the sound is crisp when knocking each other.
If there are bubbles, this is glass, not jade. It is normal for jade to have some stone lines and cracks. Can't say there are cracks or fake jade.
Agate Jian Zhen method
Agate is a rare and precious thing, and there are many fakes on the market. Most of them are made of refined turpentine, mirabilite and broken glass. To identify the authenticity, it must be rubbed in the palm of your hand, and the color, shape and smell remain unchanged. However, some people think that everything that is prone to fever after friction is genuine, which is misunderstood and unreliable.
This is not precious unless it is a few varieties, and there are few fakes now, but most of them are heated and colored, and the price is not Guiyang. You may be talking about amber.
Method for naked eye identification of gemstones
Gems can be divided into natural gems and artificial gem. When we choose precious stones and jewelry, how can we identify them with the naked eye? Natural gemstones are generally soft and natural in color, and sometimes the colors are very mixed. Several kinds of * * * in a gem, the pattern is irregular, but very delicate. Observing the gem with naked eyes under strong light, or carefully observing it with a magnifying glass for more than 5 times, sometimes you can see cotton wool, reticular or tree-root inclusions and small cracks in the gem, and occasionally you can see obvious flat growth lines. Some gems feel cold and slippery, and look wet, as if they had been soaked in oil. A good gem has the effect of "cat's eye" and "starlight" after polishing, that is, there is a white line in the gem, just like the white line in the cat's eye under strong light during the day; "Starlight" is a gem that rotates in the sun, and the reflected light shines like the blink of an eye of the stars at night. Artificial gem is generally bright, uniform and pure. After polishing, the luster is dazzling and the color consciousness is strong. Because some rare earth elements are added, there are monochromatic ones, such as black, red and yellow. There are also composite colors, such as rose red and sauce purple. But there will never be a phenomenon that several colors of natural gems are in the gem. In addition, some gems have obvious circular bubbles and traces of synthetic growth products; Obviously, the growth line is linear; Larger particles; There are many specifications of the same color; Harder ones, generally above Mohs level 6, can't be carved with a knife. Instead, these stones can mark glass.
Gems can be divided into natural gems (diamonds), synthetic gems (synthetic rubies), artificial gem (silicon carbide) and fused gems (amber). Whether it is natural or synthetic, there may be filamentous sponges, which doesn't mean anything. At present, many powder crystals are made of synthetic crystals, and those with bubbles are glass products, which have nothing to do with gems, and many synthetic products can scratch stones with Mohs hardness above six. The Mohs hardness of ruby silicon carbide synthesized mainly from sillimanite on the earth is greater than nine, and the cat's eye effect is a reflection line formed by the directional arrangement of reflected light from internal inclusions, so there will be no bubbles in the synthetic product.
Identification of true and false gems
In the sun, with a light silver pot or white satin as the lining, put the gem at a height of about five inches from the lining to make it exposed to the sun. If the light passing through the gem shows the appearance of the silver wing of Venus in the lining, it can be concluded that it is genuine. If it is a fake gem, a shadow will appear on the lining. If you put the gem in your mouth for a while, you will drool, not only will you not feel dry, but your mouth will be very cold. If the gem itself gets hot, you can conclude that it is genuine.
This appraisal is completely useless.
Emerald Jian Zhen method
Fill a bowl with clear water, and put the gem into the bowl, which can make the whole bowl appear pale green and is a real emerald; Or put Jian Zhen's gems in a copper basin, enclose them with paper, and light the white paper with fire. If fire can turn green, it is true jade; Or prepare a pot of burning coal, and put Jian Zhen's gems into the burning coal. When the charcoal smells, the emeralds will go out immediately.
Emerald is a kind of gem with many cracks. Colombia has the best quality and color, but there are still very rich liquid or crystal inclusions in it. All kinds of metals have different expansion rates, so they must not be put into the fire and will fall off completely.
Yupu identification method
Whenever people see a piece of jade (a stone containing jade), they often suffer from the inability to identify whether it contains beautiful jade, which is really a pity. In fact, its identification method is also very simple. If precious jade is hidden in the stone, look at the stone in the light at night. If there is light in the stone, just like the light color of the rising sun, it means there must be precious jade in it. On the contrary, it is not.
First, it is necessary to identify whether it is jade. Even if there are no impurities in it, it is meaningless if the price of jade itself is not big, such as Xiuyu in Liaoning.
Diamond identification method
Real diamonds glow green in the dark, just like sparks from wires. If it is a fake diamond, it can only emit a small amount of white light or even no light. Even if it glows, it looks dark and there is no flicker. In addition, the hardness of the diamond is the greatest. When the real diamond and the fake diamond are cut, the properties of the diamond will be obviously different immediately.
Due to the high refractive index of diamonds, colorful fire colors can be emitted by total internal reflection (there are many Huang Honglan) when the angle is appropriate, but in nature, not only diamonds have high refractive index, but also zircon is used to synthesize silicon carbide. If you have these, you should be able to achieve this effect.
Emerald Jian Zhen method
Fill a bowl with clear water, and put the gem into the bowl, which can make the whole bowl appear pale green and is a real emerald; Or put Jian Zhen's gems in a copper basin, enclose them with paper, and light the white paper with fire. If fire can turn green, it is true jade; Or prepare a pot of burning coal, and put Jian Zhen's gems into the burning coal. When the charcoal smells, the emeralds will go out immediately.
There are several aspects of knowledge to identify ancient jade, first of all, we must understand the decorative patterns of jade in past dynasties. This requires going to the museum to observe the exhibits and often looking through related jade albums. If you read more, you will feel that the characteristics of jade articles in past dynasties are different, and they are divided into different types according to different times. The more careful you observe, the more characteristics of the times you master and the stronger your recognition ability. If a piece of jade originally belonged to Shang dynasty, but the pattern has some characteristics of Warring States, then this piece of jade belongs to old jade, or later antique products. If you judge that this jade is a fake ancient jade made of antique, you can also judge its manufacturing age. Generally speaking, the imitation of Shang Yu appeared very late, mostly in the late Qing Dynasty.
Second, we should understand the shape characteristics of jade articles in past dynasties. This is because the shapes of many jade articles change with the times. For example, most of the jade cups in Han dynasty are thin and tall, while those in Tang dynasty are short and wide, which is completely different from the style in Han dynasty. In the Song Dynasty, the cup shape changed again. It is often judged by the shape characteristics of a jade article that it is a work of which era. The deeper you know about the shape characteristics of ancient jade, the stronger your ability to identify ancient jade. For example, imitations of Yu Ge in Shang Dynasty can often be seen in the second-hand market at present. These jade brothers are similar in shape to Shang Dynasty works, but they are often thicker than Shang Dynasty jade brothers and have no characteristics of Shang Dynasty works, so they can be regarded as imitations.
Third, we should understand the processing characteristics of jade articles in different times. These characteristics are mainly manifested in the aspects of opening, drilling, ornamentation and surface gloss treatment. In the Neolithic age, wire cutting technology appeared in jade manufacturing, and there were often traces of wire cutting on jade. If there are traces of wire cuts on a jade article, the age of this jade article can be preliminarily determined as Neolithic Age. There are many holes in ancient jade articles, and the drilling technology has changed with the times. Before the Shang Dynasty, the diameter of jades varied greatly, either large at both ends and small in the middle, or large at one end and small at the other. This kind of hole also appears in modern ancient jade, but it is different from ancient jade in the shape of the hole and the luster of the inner wall. After the Zhou Dynasty, some jades had characteristic boreholes, but the differences were very subtle, which could only be distinguished by careful observation. In terms of decorative carving methods and surface gloss treatment, jade articles in past dynasties are also different. For example, many jade articles in the Warring States and the Ming and Qing Dynasties still have glass luster, but the jade articles in the Warring States are shiny and meaningful; Jade articles in Ming dynasty are bright and hard; Jade articles in Qing dynasty are slippery and soft.
The fourth is to distinguish between new jade and old jade. On the one hand, it depends on the knife work (scar) when making, on the other hand, it depends on the corrosion degree of jade surface and the color of jade. An ancient jade may have other colors besides the color of the jade itself, mainly plate color and Qin color. Disk color is the color change produced by grinding jade in hands, which mainly appears in handed down jade. Some jades are not buried in the soil after being made, and their colors will change after being touched for a long time during the handed down process. Some people call it "cooked" and "cooked pit". Some jadeites will become "cooked pit" jadeites after being buried and discolored.
The Qin color of jade will change after burial, which is very complicated. Some jadeites have it, and some don't. Some jade is completely discolored by Qin, and some jade is partially discolored; Some are known by what substance, and some are unclear. The ancients had many names for the Qin color of jade. In the Ming Dynasty, Cao Zhao wrote "On Gegu": "Those who are as red as blood are called blood jade, and the ancients also called them ancient corpses ... those who are blackened, ancient canals and ancient treasures have low prices. Taste the loess on the jade chain and it won't wash off. This ancient soil is also. " The ancients said that there are thirteen colors of ancient jade. The colors of ancient jade recorded in Jade Records in Qing Dynasty are cinnabar red, chicken blood red, brown purple, tomato skin purple, Song Hualv, ginkgo green, okra yellow, old wine yellow, fish-belly white, brown rice white, shrimp green, snot green, rain blue, pond water pale and so on. There are many other sayings about the color of jade.
We can see the piano colors of many ancient jade, mainly black, called mercury piano; Green, called Tongqin; Ochre brown, called rust ooze; As white as fog, it is called water; Dark yellow, called Tuqin. It is observed that copper ooze, rust ooze, water ooze and soil ooze are indeed related to copper, iron, water and soil, and are caused by the erosion of copper, iron, water and soil.
Artificial dyeing of jade has a very long history. The ancients dyed jade mainly to make up for the lack of jade quality and make jade more glorious. With the increase of ancient jade collectors and the expansion of ancient jade market, dyeing jade has become an important method to imitate ancient jade and make fake antiques. The old methods of dyeing jade are different in different periods, and the color of dyed jade is also different. Dyeing jade and doing old things can be divided into three stages before and after the Qing Dynasty. People who are familiar with the color and dyeing of jadeite can often have a rough judgment on the manufacturing age of the work by looking at the dyeing on jadeite. At present, we don't fully understand the old dyeing of jade articles before the Qing Dynasty, but the antique works of the Qing Dynasty, the Forbidden City in Beijing and the Forbidden City in Taipei all have certain collections, and we can understand their characteristics as long as we often look at the exhibits. Modern jades often pursue the effect of ancient jade, sometimes they are similar, but there are always differences. If you get an ancient jade whose owner's color is different from the color of the standard works we know, we should carefully analyze whether this color is the color of ancient jade that we don't know, or whether it is artificially made, so as to judge the old and new works.
There are many books identifying ancient jade on the market. Interested parties can buy it and have a look. The method introduced in it is very detailed. There is also a website upstairs for reference. But to be honest, it is a bit unrealistic to learn to identify jade articles by reading books and surfing the Internet. The key is to contact more genuine products, accumulate hand feeling and practical experience, and find relevant experts to learn some skills.
The identification of jade ornaments should be based on hardness, transparency, color, luster and spots. Real jade is very hard and wear-resistant, crystal clear, pure and beautiful in color and sparkling. If you can see cracks, fibrous cotton threads or dark wounds in jade, it is inferior jade. All fake jade has wrinkles on the surface and bubbles inside, which is light in weight and low in hardness, and the sound is crisp when knocking each other.
Agate Jian Zhen method
Agate is a rare and precious thing, and there are many fakes on the market. Most of them are made of refined turpentine, mirabilite and broken glass. To identify the authenticity, it must be rubbed in the palm of your hand, and the color, shape and smell remain unchanged. However, some people think that everything that is prone to fever after friction is genuine, which is misunderstood and unreliable.
Method for naked eye identification of gemstones
Gems can be divided into natural gems and artificial gem. When we choose precious stones and jewelry, how can we identify them with the naked eye? Natural gemstones are generally soft and natural in color, and sometimes the colors are very mixed. Several kinds of * * * in a gem, the pattern is irregular, but very delicate. Observing the gem with naked eyes under strong light, or carefully observing it with a magnifying glass for more than 5 times, sometimes you can see cotton wool, reticular or tree-root inclusions and small cracks in the gem, and occasionally you can see obvious flat growth lines. Some gems feel cold and slippery, and look wet, as if they had been soaked in oil. A good gem has the effect of "cat's eye" and "starlight" after polishing, that is, there is a white line in the gem, just like the white line in the cat's eye under strong light during the day; "Starlight" is a gem that rotates in the sun, and the reflected light shines like the blink of an eye of the stars at night. Artificial gem is generally bright, uniform and pure. After polishing, the luster is dazzling and the color consciousness is strong. Because some rare earth elements are added, there are monochromatic ones, such as black, red and yellow. There are also composite colors, such as rose red and sauce purple. But there will never be a phenomenon that several colors of natural gems are in the gem. In addition, some gems have obvious circular bubbles and traces of synthetic growth products; Obviously, the growth line is linear; Larger particles; There are many specifications of the same color; Harder ones, generally above Mohs level 6, can't be carved with a knife. Instead, these stones can mark glass.
Identification of true and false gems
In the sun, with a light silver pot or white satin as the lining, put the gem at a height of about five inches from the lining to make it exposed to the sun. If the light passing through the gem shows the appearance of the silver wing of Venus in the lining, it can be concluded that it is genuine. If it is a fake gem, a shadow will appear on the lining. If you put the gem in your mouth for a while, you will drool, not only will you not feel dry, but your mouth will be very cold. If the gem itself gets hot, you can conclude that it is genuine.
Emerald Jian Zhen method
Fill a bowl with clear water, and put the gem into the bowl, which can make the whole bowl appear pale green and is a real emerald; Or put Jian Zhen's gems in a copper basin, enclose them with paper, and light the white paper with fire. If fire can turn green, it is true jade; Or prepare a pot of burning coal, and put Jian Zhen's gems into the burning coal. When the charcoal smells, the emeralds will go out immediately.
Yupu identification method
Whenever people see a piece of jade (a stone containing jade), they often suffer from the inability to identify whether it contains beautiful jade, which is really a pity. In fact, its identification method is also very simple. If precious jade is hidden in the stone, look at the stone in the light at night. If there is light in the stone, just like the light color of the rising sun, it means there must be precious jade in it. On the contrary, it is not.
Diamond identification method
Real diamonds glow green in the dark, just like sparks from wires. If it is a fake diamond, it can only emit a small amount of white light or even no light. Even if it glows, it looks dark and there is no flicker. In addition, the hardness of the diamond is the greatest. When the real diamond and the fake diamond are cut, the properties of the diamond will be obviously different immediately.