The method of identifying natural jade with the naked eye is worth learning

Reading is a kind of wisdom, sharing is a virtue

Recently, many friends have asked questions about jade identification on the Internet. Many friends like jade but stay away from it just because of the trouble with fakes. In view of this, Xiaoping combines theoretical knowledge and what he sees in the market to summarize the knowledge on jade identification, hoping to help everyone.

Jade has been sought after by the Chinese people since its birth. Everyone likes beautiful jade, which has also attracted the attention of counterfeiters. It is now impossible to verify when the earliest processed jade appeared on the market. A common saying is that around the time of reform and opening up, the strong expansion of domestic demand made Hong Kong businessmen smell the business opportunity. They began to study how to increase the market value of low-grade jade. The most direct method was to use chemical treatment to increase the water head of jade , thereby greatly increasing the commercial value of jade. Counterfeiting and identification have always been like a spear and a shield. However, before the emergence of infrared absorption spectroscopy detection, counterfeiting was always like the devil is always one step ahead of the saint. It was often a long time after a new counterfeiting method came out that people developed the corresponding detection method. This relationship has continued to this day.

The jade identification standard that everyone agrees on now is to divide jade into four grades: A, B, and D. Grade A jade is natural jade that has not been artificially treated, but includes jade that has undergone optimization processes such as burning, baking, and waxing; Grade B jade is jade that has been treated with acid washing and filling with glue; Grade C jade is jade that has been artificially dyed; Grade D jade is jade that is a replica of jade. The most commonly seen jade in the market now is A-grade jade, while B-grade, B+C-grade and D-grade jade are common in tourist spots and supermarket counters. However, it should be pointed out that there is also a kind of jade that is not common in the mainland market, which is between A-grade, B-grade and C-grade jade, such as the jade with polishing powder and the jade with weak acid wash and wax dip. Among these, the most deceptive to ordinary consumers are ordinary B+ C grade jadeite and dyed quartzite, while the most likely to cause trouble for practitioners are high B and wax-soaked jadeite.

(The following four pictures are obvious B+C products. If you still can’t tell the difference, it is recommended that you bring the certificate with you when you buy the goods)

(The following four pictures are obvious B-grade jades. If you can tell them at a glance, it means you have a certain level of jade identification skills.)

(The following four pictures are obviously D-grade jade. The first one is a chalcedony Guanyin which is relatively easy to identify. The second one is a quartz water jade. The third one is a Malay jade. The fourth one is a dyed quartzite which is more common in the market now. It is quite deceptive and if you buy it as jadeite, you will suffer a great loss.)

(These three pictures are worth your attention. The first one is a B-grade jade made of dry green, the second one is a B-grade jade made of jade similar to dry green, and the third one is a fake B-grade jade)

(These two pictures clearly show how the same jade material changes from A-grade to B-grade. The leftmost picture in each picture is A-grade, the white material in the middle is the state after pickling but not dyed or injected with glue, and the rightmost picture is the state of the sheet material after injection and polishing. The finished products carved from this material are B-grade and B+C-grade)

Identifying jadeite is a systematic project, which includes two types of identification: instrument identification and identification by the naked eye. The instrument identification and testing will not be repeated here. Relatively speaking, more practical for general consumers is identification by naked eye, but identification by naked eye is a process that requires gradual accumulation of experience. Simply put, identification with the naked eye requires analyzing the following aspects of the object you see: What is the quality, water quality and color of the object? Is the germplasm harmonized? Are the colors natural? Are the colors and shapes natural? Look carefully (or use a magnifying glass) to see how the colors are distributed. When you weigh the real thing, does it feel like A-grade jade is heavy? Does the luster of the real object have the near-glass luster of jadeite? Is the base color too clean? Are there any observable traces of processing, such as acid etching patterns, color mesh distribution, etc.

Below, Xiao Jin will share some experiences with you. If there are any shortcomings, I hope you can give me some advice.

1. Acid-etched patterns that may be observed in B-grade jadeite. Acid-etched reticulation refers to the process of jadeite being acid-washed, filled with glue, and then carved and polished, where the hardness of the colloid filling the cracks is significantly lower than that of the surrounding jadeite, so it is significantly cut and polished to form more concave grooves. These small grooves are distributed along small cracks and gaps between particles, and when connected together they form a spider-web-like surface pattern. Acid etching reticulation is an important identification feature of B-grade jadeite. Obvious acid etching reticulation can be observed with the naked eye, while subtle acid etching reticulation is not easy to find even by an inexperienced person under a microscope. The obviousness of the acid etching pattern is directly related to the following factors:

(1) The particle size of jadeite. The coarser the jadeite grains that make up the jadeite, the more obvious the acid etching patterns tend to be. The patterns of B-grade jadeite with a bean-like structure can be observed with the naked eye and under a 10x magnifying glass. The fine particles must be observed under a gem microscope to be seen.

(2) The degree of acid etching and dissolution of jadeite. The more intensely the jadeite is treated and the more resin is filled in, the clearer the acid etching pattern will be. Conversely, the pattern will be less clear.

(3) Polishing technology: For B-grade jadeite polished with a floppy disk or a vibration polisher, the acid etching pattern is more obvious. For B-grade jadeite that is polished with improved diamond powder, the polishing process may not be obvious or even undetectable.

(4) Acid etching patterns must be observed on well-polished areas. On poorly polished surfaces, there are too many similar phenomena to acid etching patterns, such as wear marks, sand holes, pits, and boundaries between particles, which are difficult to distinguish without experience.

(5) The acid-etching texture is different from the normal "orange peel effect" of jadeite. When the crystal particles are relatively coarse, the acid-etching texture is much more obvious than the orange peel effect. Acid etching patterns generally form a relatively regular network, while the orange peel effect is relatively irregular. The orange peel effect is caused by the different hardness of different crystal particles in the jadeite aggregate. The softer particles are also eroded during the polishing process, forming a concave polishing surface. The boundary between the concave particles and the surrounding harder particles has a smooth transition slope. The crack network of B-grade jadeite is composed of small concave gaps formed along the boundaries of the grains. Although there are differences in hardness between particles of B-grade jadeite, and it will also form an orange peel effect, because there is resin with lower hardness between the particles, there is a lack of a sloped transition zone between the concave and convex surfaces.

2. Acid-etched, resin-filled cracks and resin-filled corrosion pits that may be observed in B-grade jadeite. The larger cracks in B-grade jadeite with poor workmanship and texture will be filled with more glue, presenting a concave surface after polishing. Under reflected light, through a microscope, a greasy (weakly reflective) surface can be seen, like a ditch with flowing water. Cracks that are not filled with glue will not have this kind of surface, and will have no oily luster, just like a dry ditch. It should be noted that cracks with concave arc surfaces and waxy luster are not necessarily glue-filled cracks, because the waxing process of jade products can also cause this phenomenon. Dissolution pits are caused by the presence of certain locally enriched minerals in jade that are easily corroded by acid and alkali, such as chromite, mica, and albite. These minerals are dissolved during the processing to form larger spaces. In the subsequent filling treatment, a large amount of resin is filled in the voids. When these voids filled with resin glue are cut and ground to the surface of the jade, the hardness of the resin glue is much lower than that of the constituent minerals of jade. Therefore, it is easily eroded during the polishing process, forming relatively deep pits. Even bubbles enclosed in the glue can be observed.

3. B-grade jadeite has a relatively clean base color, without impurities and no grayish-yellow color. Since B-grade jade has undergone acid washing and bleaching, the oxides and other fusible impurities in the jade are dissolved, and the yellow base and dirty bottom are removed, but the light green, blue water color and pink lotus bottom color will still exist. Observe the white part of the jade carefully. If it is B-grade jade, it will be particularly white, without impurities and gray and yellow components. However, in order to make B-grade products more like A-grade products, counterfeiters nowadays sometimes deliberately dye the products a grayer or dirtier color before filling them with glue. This kind of B+C is more deceptive. For specific identification, please refer to the knowledge of color identification discussed later.

4. B-grade jadeite may have unclear grain boundaries. The coarse-grained A-grade jadeite should not be able to achieve a good water head, but B-grade jadeite subverts this common sense. This is the inharmonious quality of B-grade jadeite. Because the grains of B-grade jadeite are filled with highly transparent resin glue, which fills the gaps between the grains and enhances the transmission of light, when observing the internal structure of B-grade jadeite, you will find that the boundaries between the grains are blurred. The difference is particularly obvious when comparing coarse-grained B-grade jadeite with natural jadeite. When natural jade is illuminated by side light, the propagation of light is obviously blocked by the boundaries or micro-cracks between the jade grains. The granular structure in the jade is very clear, while the grains of B-grade jade with the same coarse grains appear unclear, and the water head is much better than that of natural jade of the same grade.

5. B-grade jade may have a greasy feel. Many experts can see the "greasy feeling" of B-grade jadeite. After processing, the hardness and gloss of the colloid are far lower than that of natural jadeite. Therefore, the more intense the acid washing and colloid filling process of the B-grade jadeite, the worse the gloss of this B-grade jadeite will be compared with the natural A-grade of the same grade. For example, natural ice jadeite definitely has a glassy luster, while B-grade ice jadeite may have an oily luster or a relatively poor near-glass luster, which is significantly lower than natural A-grade ice jadeite. However, high B goods generally have a glassy luster because the B goods process is relatively light. A-grade jadeite of relatively poor quality may also appear greasy if not polished properly, so specific problems require specific analysis.

6. The knocking sound of B-grade jadeite is dull. This method is very effective in identifying general B-grade jade bracelets, but it is ineffective in identifying smaller jade pendants and jade ring faces, as well as high-grade B jade with excellent workmanship. The knocking sound of B-grade jadeite bracelets is mostly dull and hoarse, not crisp enough, which is completely different from natural jadeite. Instead, it is similar to the sound of a natural water foam jade bracelet . When using this method to identify a pendant, you cannot hold the jade piece with your hand. It is best to hang the jade piece with a thin wire and gently tap it with another solid piece of jade. It should be noted that if natural jade has cracks or a loose texture, it will also produce a hoarse and dull knocking sound. Since high-grade B jadeite is made with high-strength resin glue, the amount of glue filled is also less. Therefore, the crispness of the knocking sound of such B-grade jadeite bracelet is almost the same as that of A-grade jadeite.

7. Study the color hue of B+C grade jadeite and the distribution pattern of its color and shape.

The color tones of B+C grade jadeite are often too bright. For example, if it is dyed green, it tends to be mostly yellowish green and light green. If it is dyed purple, it tends to be a darker purple that is rare in natural jadeite. If it is dyed red, it tends to be a brighter red. They often deviate from the natural color distribution pattern. For example, natural red jadeite is generally accompanied by grayer or yellower colors, but in recent years, blue or grayish green colors have also appeared.

The color of B+C grade jadeite is darker in locations with cracks, because the color is mostly distributed along the cracks like tree roots, or is dyed into clumps or blocks. The distribution is extremely unnatural. For example, the more positive green color of natural A grade jadeite is impossible to be distributed along the cracks like tree roots. Only the oily green color of natural jadeite is distributed like tree roots.

When you magnify or observe the color of B+C grade jadeite carefully, you may find that the dyed color is composed of filaments of a loofah-like structure distributed along the gaps between particles and on the surface of particles. This is especially obvious under transmitted light, which is completely different from the vein-like distribution of color roots in natural jadeite .

The color of B+C grade jadeite is often dyed into an uneven form, and may be dyed into block-shaped spots or color bands similar to the color roots of natural jadeite. However, the dyed color usually has a blurred boundary with the base color, and the concentration changes rapidly, usually changing from a darker color to the base color part, which is inconsistent with the natural color distribution pattern. The boundary between the colored part and the base color part of natural colored jadeite is generally uneven and irregular, with clear boundaries in some places and blurred boundaries in others. What’s important is that the natural green is actually a very long natural dyeing process (green is often caused by the diffusion and deposition of chromium-containing solution along early cracks and particle gaps when jadeite is first formed. The color diffuses slowly, and the color is dark when the chromium ion is concentrated and light when the chromium ion is low). Therefore, the natural green is unevenly distributed in shades, and the transition from the dark color part to the base color part is often gradual. Therefore, there are color transition zones of varying widths between the color root and the base color of natural jadeite, and block color spots like B+C are rarely formed. If the jade is dyed purple, the dye will be concentrated in the cracks and gaps between the particles, which is different from the flaky and blocky distribution characteristics of natural purple jade. If it is dyed red jadeite, the dyed red position generally does not have the foggy distribution pattern of natural red jadeite. The dyed red jadeite may appear in the internal jade flesh. In addition, it can also be distinguished from natural red jadeite by its hue and background color.

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