Jade "A, B, C, D" goods knowledge encyclopedia

Since ancient times, the Chinese people have the most respect for jade, and the advanced jade is the favorite of the Chinese people. Therefore, some people try their best to enhance the color to cater to their preferences. The so-called (beautification) is to treat the inferior gemstones with poor color by artificial methods or by adding or not adding color materials to make the original unpopular appearance. Improved into a charming appearance, enhance the sense of value, in fact, the real value has not increased, but the price has increased a lot. For example, the diamond waist is immersed in a blue aqueous solution in the early stage, and the blue pigment is attached to the waist surface of the diamond after being picked up to dry. The blue color is lowered by the light reflection, and the color level of the diamond is improved. This method is simple, but it is also easy to fade and the flaw can be seen with a magnification of 10 times - a granular pigment attached to the waist surface of the diamond. With the advancement of technology, the processing method is more precise and less noticeable (such as the conversion of yellow-brown diamonds into blue or green diamonds by radiography), and heat treatment and diffusion heat treatment to give low-grade blue colorless or milky colors. Color gems, changed to high-priced rubies or blue sapphire or golden sapphires. The treatment methods are endless, varied, and difficult to prevent, and jade is no exception. According to its landscaping method and identification method (A goods), (B goods), (C goods), (D goods) as follows:

1. A cargo (Allowing): waxing treatment

Emerald is an opaque to translucent gemstone. The emerald green we see is the result of some light in the sunlight or white light being absorbed by the emerald and reflecting the green light. The color of the jade is to be colored (concentrated), colored (positive), and colored. The four elements of (positive) and color (even) must have a dense and smooth surface in order to have a mirror-like reflected light. The jadeite is often mixed with other materials to form a rock, so the structure is not uniform, after polishing The surface is not very smooth; under the magnifying glass, it is like the shark skin concave and convex unevenness, and the reflection ability is greatly affected. For this reason, after the completion of the honing process, the last and most important procedure (buffing), then soaking In the fruit acid, the iron or other impurities on the surface are slightly rinsed (this process is called "de-yello"), and in particular, it is further immersed in the wax solution to infiltrate the wax to fill the cracks and small holes to improve the reflection. Ability to increase shine. This practice has been going on for many years and is accepted by the average person. It is called (A goods) or (Allowing Jadeite) among the jade industry.

Second, B goods (BleachedandPolymerimpregnatedJadeite) bleaching injection treatment

Emerald bleaching and infusion rubber processing has become very popular in the jade market, especially in Taiwan, Hong Kong and Japan. No matter whether it is high-grade goods or old-fashioned species, it is reported that 80-90% of high-end goods have been treated. . The method consists of two main stages: the first stage is Bleaching, also known as fading, the boulder that has been cut into pieces, or the jade that has been honed, and the chemical treatment removes the annoying Sepia or grayish black (may be caused by the filling of iron compounds in cracks). The second stage is to inject the polymer (loyer-Impregnating), even adding green pigment. The jade, which is processed through these two stages, is called BlachingandploymerImpregnatedjadeite in English, and its first letter in English is (B), so the jade industry is referred to as (B goods). Until now, this treatment was limited to green or white jade, and other colors such as purple or nephrite were not found.

(1) Procedure for bleaching and injection molding

The first stage of bleaching: jade stone (wool), or cut into slab-like rough or honed jade such as ring face, pendant or bracelet, etc., immersion chemicals to remove brown yellow iron oxide between cracks or particle structure. According to various sources, hydrochloric acid and fruit acid are the most commonly used bleaching agents, and other sodium compounds are often used to bleach jade. Depending on the degree of pollution of the jade or the source of the pollution, some may only be immersed for a few hours, but some will be immersed for a few weeks to be effective. When the color presented is judged to have reached the maximum improvement, it is taken out and continuously cleaned with water. Of course, there is also soda water to "neutralize" the acid remaining on the jade. At this point, it is normal operation. Many kinds of gemstones such as emeralds are treated like this before emerald, and even the corals are washed with dilute hydrochloric acid instead of polishing. Such products are naturally untreated because no other materials are added.

Stage 2: If bleaching is complete, all or most of the tan smudges between the cracks or particles are removed, but the white or pinkish green veins are more pronounced and not good looking. The bleached jade leaves the pores by removing the stains, making the fragile state, even the lowest quality bleaching jade, crushing with the force of the fingers. If it is not treated, it will be worn in jewelry. After a long time, these pores will be filled with dirt and grease, which is even less beautiful. Therefore, it is necessary to carry out the second stage of operation, injecting polymer, sometimes only wax, but most of them. Resin is injected to replace the removed material. To fill the pores and consolidate the loose jade, some technicians inject the dye together with the polymer (Ng1990), and the residual polymer is removed after the filling is completed.

(2) Identification method:

The gemstone properties of bleached and injected jadeite were determined. The refractive index and spectrum (handheld spectrometer) were not significantly different from those of the untreated ones, but in specific gravity, ultraviolet fluorescence reaction, hot needle reaction, hot needle reaction test and high magnification. There are significant differences in characteristics (appearance), etc., which can be used to test bleached injection products. Recently, the new instrument infrared spectrometer developed for jewelry identification is expensive and requires high technology, but the most accurate. It is described as follows:

(1) Drop a small drop of pure hydrochloric acid on the untreated jade and observe for a few minutes (about 1-20 minutes). There will be many (small round sweat beads) around the droplet. This reaction is a crystalline particle of jadeite with small cracks and sub-pores and capillary action. When the bleached gelatin jade is tested in the same manner, the rubber is filled with the sub-pores without such a phenomenon of small round sweat. Note that in dry heat, especially in air-conditioned rooms, this test, because hydrochloric acid will evaporate before you see the reaction, so you must constantly drop hydrochloric acid.

(2) With the reflected light of the microscope, the filler reaching the surface crack can be observed. Low-grade jade with poor gloss may also find white spots on the jade sheet; it is caused by negligence during processing; in the sample of the polished surface, it is sometimes seen that the material bubbles of the filler or the cotton-like fiber aggregates are gathered in the transparent glue. In the material, even the rubber residue can be seen in the engraving shallow trench, depression, small pit and so on.

(3) UV fluorescence reaction

Most natural untreated jadeites do not respond to UV radiation. Some of the long-wave ultraviolet rays show a light to moderate yellow color in white, and weak or no reaction to short-wave ultraviolet light. The green part did not respond. The bleached and injected jadeites all react to the long-wave ultraviolet rays. In the short-wave ultraviolet irradiation, it is dull or non-reactive. It shows a weak to strong blue-white fluorescence under long-wave ultraviolet light, sometimes more pronounced in white, which is roughly from the glue that is infused.

Therefore, the appearance of blue-white to yellow-green fluorescence under long-wave ultraviolet rays provides a useful indicator for bleaching and embedding jadeite. However, this test must be carried out in the darkroom. If it is bright, the fluorescence cannot be seen, and the fluorescence reaction of the gemstone is used for reference. It must be determined by other methods. Of course, many high-end b goods now, this may be invalid.

(4) Knock:

The identification of jade quality and grade, the ancient Mingxun six-character 诀: color, transparency, uniformity, shape, knocking, photo, for the jade industry often hang on the motto, which "knock" in the identification of B goods can be sent use. Large items such as jade bracelets are lightly tapped with coins, and if they are natural untreated high-grade goods, they will make a crisp and sweet sound, while B goods will give a gloomy, dull sub-sound. The theoretical basis is that the rubber or fracture in the jade structure blocks the sound waves, while the untreated sound waves are unobstructed.

(5) Infrared spectrometer:

Infrared spectrometers are available in research or academic institutions. They are expensive and difficult to operate. They are available in general jewelry accreditation laboratories. However, it is most accurate to identify whether jadeite is treated with glue. The instrument for testing the bleaching and injection molding by this instrument can find a strong absorption peak at about 2900 cm-1 in the middle infrared region. Further, the glue (polymer) used in the test is mainly composed of three kinds of polymers such as wax, phthalate and opticon. Among them, Resin No. 224 is most commonly used.

Third, C goods (Coatingjadeite) coating treatment

The method of coating treatment is to coat a surface of white jade (which can be replaced by other decorative stones such as jade), and coat a thin layer of green plastic film to turn the original white jade into a green and transparent "Crown Green". . In fact, several gemstones have been modified to improve the color of the gemstone. Surfaces such as faceted natural gold jade are covered with a layer of green material to pretend to be emeralds (kane1982); colorless steel jade beads are covered with red material in their bead holes; starlight colorless sapphire is covered with plastic to pretend to be star red Bao and so on.

This surface-coated jadeite has no reaction under the color filter and ultraviolet light. The general identification method is to magnify and examine the characteristics of the microscope: (1) the surface loses the rough surface unique to the jade (pit pit); it is smoothed by the film wrapping (2), the dyed color of the film can be seen as a fine point. The dots are scattered on the joint surface of the film and the jade. Especially the blue table on the bottom is the clearest. (3) Turn over the jade, and when you look at the sky, you can see that the color is concentrated around the jade. (4) Sometimes you can see the original color of the jade in the damaged area of ​​the film (Figure 6). It is also possible to pierce the film with a hot needle or a pin, but this method must be applied with caution. Alternatively, a spectrometer can be used to observe a thick absorption spectrum in the red zone.

Fourth, D goods (DyeingJadeite) dyeing treatment

The jadeite that is currently dyed is called "C" "Colored" Jadeite. In fact, in the jewelry literature, the word "Dye" is used for artificial dyeing, and "Colored" refers to natural coloring. At that time, it is still unknown that it has not been covered ( CoatingJadeite) quality, so the dyed jade is hardly planted as ColoredJadeite and called "C goods", you can see if there is no preconceived prejudice, you may wish to correct it. Although jade can be dyed in various colors, it is more common to dye green and purple, especially green. Not only bare stone and jade can be dyed, but also sliced ​​and rough (raw material) can be dyed. The dyeing process consists of two steps of heating and adding high pressure. Heating must be carefully and carefully heated to promote the opening of the pores of the jadeite, and then spread the dye into the entire surface of the jadeite with high pressure.

Early dyeing was only used to complete the honing of the bare stone, and it was closed and the door was secretly carried out, and no one admitted to doing the dyeing work. This soil dyeing takes a long time and often has to be repeated 6 to 12 times in order to obtain good results. First of all, the jadeite must be heated slowly. This must be skill and experience of training. Otherwise, it will heat up too quickly and cause cracking. Therefore, it is not possible to directly heat the jadeite. Just like the fried chestnuts, put the jade in a pot filled with iron ore (small chestnuts with pebbles) indirectly for 5-15 minutes to make the heat even, and then put it into the dyeing solution. Dyeing the dye into the cracks, main veins and pores for dyeing purposes. Nowadays, scientific and technological progress has been dyed on a large scale, and it is no longer heated with iron ore, but replaced by modern equipment such as ovens, pressure cookers and so on.