Let's talk about the identification method of B-grade jadeite

Today we continue to share with you the identification method of B-grade jadeite. Compared with C-grade jadeite, Mingyue feels that B-grade jadeite is more harmful to the human body, so jade friends must be on guard against B-grade jadeite when purchasing jadeite. Neither B goods nor C goods have the possibility of maintaining or increasing their value! As for the possibility of reselling it, it is very small unless you are also going to "cheat".

Before identifying A and B grade jadeite, we must first clarify the definitions of A and B grade jadeite. Grade A jade is natural jade that has not been artificially processed. It refers to the variety of jade that has not been artificially changed in appearance, durability, or usability except for cutting and polishing. B-grade jade products are jade products that have been corroded by strong acids and then injected with organic matter to make up for the structure and strength destroyed by the acid.

Key point: Products that change the internal structure through glue or wax injection are B-grade products. Natural A-grade jadeite bracelets are dipped in wax to protect moisture after they are finished. This is only a layer of wax on the surface and does not affect the internal structure, so it is still A-grade (so jadeite needs to be dipped in wax for maintenance, especially in dry areas, and needs to be dipped in wax for long-term storage)

Here everyone must distinguish the difference between wax dipping and glue injection or wax injection. It can be said that almost all jade articles will have wax dipping. The reason is very simple, which is to protect moisture. This is necessary for Hetian jade, Dushan jade, Xiuyan jade, and jadeite. It can even be said that as long as it is "jade", it will be treated with wax dipping. This is a normal way to maintain jade, not fake or anything like that!

B goods, Bath, originally means to rinse, and here it refers to acid-washed. C goods, Color, means dyed.

Of course, jade is not washed with water, but soaked in strong acid to corrode and dissolve impurities and stains, making it clear and bright. Jade that has been washed with strong acid has a loose structure, and the cracks after acid etching must be filled. A commonly used method is to inject transparent resin using the vacuum negative pressure method. The refractive index of this resin is close to that of jade. After polishing, it is almost indistinguishable from high-end A-grade jade.

The bleaching and filling process of B-grade jadeite is mainly to remove impurities that affect the color and transparency of the jadeite, fill and cover up the cracks in the jadeite to reduce the brittleness of the jadeite in order to increase the beauty of the jadeite, increase the selling price and obtain high profits. The market often calls it B-grade jadeite. If colorant is added during filling, it is called B+C jadeite. Therefore, the objects of bleaching and filling treatment are generally medium and low-end jewelry and blanks.

Let’s take a look at the processing process of B-grade jade. The first step is to select the materials. The jade that undergoes B processing is generally medium-to-low-grade jade with medium-coarse grain structure and many cracks. Such as bean-type, indigo, white-bottomed green and other materials, while jadeite with fibrous fine-grained structure and few cracks is generally not treated in this way. The bracelet materials to be processed need to be tied and fixed with acid and alkali resistant stainless steel wire. The purpose is to prevent the bracelet materials from colliding with each other during the processing, especially the bracelet material structure becomes loose after processing, which can easily cause breakage.

Look at the one above, it’s dirty, dark, has a lot of impurities and cracks. . No one wants it if we sell it directly, so we have to "beautify" it! ! After taking off the bracelet, you must first fix it with wire, because after being corroded by strong acid, the structure becomes very loose and it will fall apart if not fixed. .

Place the jade raw material to be processed into a mixture of concentrated nitric acid and hydrofluoric acid and heat it. The temperature range is between 90 degrees Celsius and 100 degrees Celsius. If the temperature is greater than 100 degrees, the acid will boil and become extremely volatile, and the acid will lose its effect in a short time. At a temperature of around 90 degrees, the reaction rate can be accelerated to exert the effect of acid on the ferrous ions and ferric ions in jade to remove the yellowness and dirty bottom, and volatilization can be reduced to extend the service life of the acid. After a period of reaction, take the jade raw material out of the acid solution and put it into clean water. Increase the temperature, take it out after boiling, replace it with clean water, and heat it to boiling again. Repeat this 3-4 times in order to clean away the acid that has seeped into the jade. As the coloring matter between the jade grains or in the cracks is dissolved by the acid, the base color of the jade turns white. Dry and opaque, this indicates that the structure of the jade has been damaged to a certain extent.

After acid treatment, the jade raw material washed with clean water is placed in a caustic soda solution and heated to about 90 degrees. This not only neutralizes the acid, but also, due to the action of strong alkali, accelerates the expansion of cracks and further loosens the jade structure. The above acid treatment and alkali treatment processes are repeated many times, which can be adjusted according to the size of the raw material particle size or the density of the structure, generally lasting dozens of days. Due to the different mineral compositions of jadeite, the acid etching rate and treatment efficiency of jadeite samples vary greatly during acid treatment. Some jades are not suitable for filling even after acid treatment. Generally speaking, the more impurities there are, the faster the acid etching speed. The shorter the processing time required. At the same time, the degree of loosening and destruction of the jade structure is related to the density of the original jade structure, as well as the concentration of strong acids and alkalis and the length of treatment time. If the original jade raw material has finer and denser grains, the soaking time will be shorter. The smaller the size of the steel, the less damage its structure will suffer; if the original structure is coarse and loose, and the processing time is long, the structure will be more severely damaged. During the treatment process, the acid and alkali solutions are easy to evaporate at the reaction temperature, the liquid needs to be changed frequently, and the concentration of the acid and alkali solutions is high, which increases the cost. However, the processing time can be shortened accordingly; conversely, the cost will be reduced if the fluid is changed less frequently. The concentration of acid and alkali solutions decreases due to volatilization, which prolongs the processing time. Therefore, in order to achieve the purpose of purifying the loose jade raw materials, it is necessary to select economically reasonable acid and alkali concentration, liquid change times, treatment temperature and treatment time according to the raw materials to be treated. After repeated acid and alkali treatments, the structure of jade is very loose, and particles will fall off with a light touch. Therefore, steel wire fixing effectively reduces the breakage rate of the bracelet material.

This is what it was like after it came out. It’s white!

The impurities, moss and secondary colors inside have all been corroded away, making it pure white! Isn’t it beautiful! Equivalent to a mummy. . No one wants this, there is another step! Glue injection!

Enter the glue injection machine, place it properly, add organic glue, vacuum it, and expel the bubbles in the jade products. The glue is then pressed into the jade product by atmospheric pressure. This process also takes 3-5 days. .

The process of acid and alkali treatment of jade is carried out along the gaps between the particles, resulting in a loose structure. Filling with resin is not only for the purpose of cementing the loose structure to improve its strength, but also for the purpose of increasing its transparency. After acid and alkali treatment, the jade is neutralized and cleaned, then placed in an oven for drying and then transferred to an autoclave. After being sealed and evacuated, the epoxy resin and curing agent diethanolamine are mixed in a certain proportion, heated to reduce its viscosity and then added to the autoclave. At this time, continue to maintain the vacuum state for a while, then turn off the vacuum pump, restore normal pressure and then add a certain pressure in the autoclave. The purpose is to allow the resin to completely enter the loose structure of jade and remove the jade raw materials. The B treatment process is completed by heating until the surface is solidified. The processed materials can be subjected to post-processing such as polishing, shaping, and carving.

This is what it looks like after it comes out, very different from the one above. . . Look at the picture below, moist, transparent and clean! !

Then after further processing and polishing, it becomes a beautiful jade product. Compare it with your untreated self, and you will see how much the change is.

Big transformation, now you can enter the counter! ! !

After looking at the processing process, you will know why you must buy A-grade jadeite?

Here are the reasons:

• First: After acid etching, the structure of B goods changes and becomes loose.

• Second: The organic glue used for filling has a short lifespan and will turn yellow and age after a few years of wearing. . The glue itself also contains some harmful substances.

So when buying and wearing, try to choose A-grade products (if you must spend 200 yuan to buy an "ice type" bracelet, I'm afraid it can only be B-grade.)

How to identify? Through the above process, it is not difficult to find some characteristics of B-goods.

Acid etching will definitely leave etching marks, and the luster of the surface will be dim. A-grade jadeite has a glassy luster and is smooth. There will be a fluorescent reaction inside the injected glue (Ni salt glue). The fluorescent reaction can be checked with a purple light!

It is obvious from the picture above which one is the A product and which one is the B product! Because the acid etching process causes the entire structure to change, no matter how you polish it, the acid etching marks will still exist, and the gloss will be different from that of the A-grade products! If you scratch it with your fingernails and feel any resistance, it is likely to be a B-grade product.

In fact, there are very few pure B-grade products now, but there were very many of them more than ten years ago. Some friends sent me photos and said that she bought it ten years ago and spent 500 yuan at the time. As you can see from the picture, it is glue injected. .

With the improvement of consumers' awareness, the current B-grade jade is more likely to be injected with glue on the original color. In other words, the green color of the bracelet is real (the green color of jade itself cannot be removed by acid etching). The impurities are removed and the water quality is improved to make B-grade jade. As shown below:

The one on the left is bean-type, with coarse and dry grains. The one on the right looks much more transparent after being injected with glue. And then look at the green color, it's really the non-dyed kind that looks floating. . . Those who didn't know the truth immediately brightened up their eyes and asked about the price. It was so cheap, they thought they had picked up a great bargain! If you buy it, you will be cheated!

I still need to remind everyone that whether it is B-grade or C-grade jade, its main purpose is to "beautify" jade and improve its quality, so that customers will like it at first sight. Therefore, when purchasing jadeite, the pursuit of "perfection" is a big obstacle. Mingyue's experience is that you should be careful with any "very beautiful" jadeite, try to find flaws, and judge the authenticity and whether it is B or C grade jadeite based on the flaws.

Another very deceptive type is the high-gloss and high-fluorescence glue-injected jade products. Impersonating ice type and glass type.

Natural jade has no fluorescence. Good water head means it has glue and luster. . .

Summarize the characteristics of B goods:

1. The acid etching marks on the surface cause the gloss to be dim and there is a sense of resistance when scratching with fingernails.

2. Although the glue seems to improve the water quality, the glue is injected too evenly, while natural jade is uneven.

3. The glue will have a fluorescent reaction and will turn yellow and age after wearing for a long time!

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