Identify B-grade jadeite from five aspects

Jade is loved by Oriental people and is also known as the "Oriental Gem". As a high-quality jade, jade has been cherished since ancient times due to the bright colors, moist texture and beautiful appearance of natural gems. However, natural high-grade jade is very rare and expensive. In order to increase its value, artificial processing methods are often used to improve the color and transparency of jade. Since there is not much difference in appearance from natural jade, you should be cautious when purchasing.

The color and transparency of jade are signs of its quality. Natural jade sometimes contains metal ions such as iron and manganese, which make the jade mixed with black, brown, gray and other colors to varying degrees, affecting its brightness. If there are defects such as black, brown, or gray in the base color, the value will be significantly reduced. In order to remove these dirty colors, chemical bleaching is usually used to remove them, making the jade bright in color and pure and transparent in texture. This is B-grade jade. The value of A-grade and B-grade jadeite with the same appearance varies greatly, so when buying jadeite, you should pay special attention to B-grade jadeite to avoid financial losses.

So, how to identify B-grade jadeite? First of all, you need to understand the production process of B-goods. The early production of B-grade jade was simple. Acid was used to remove the discoloration and stains on the jade, and then a layer of wax was applied on it. At first glance, it looked no different from natural jade. However, over time or when exposed to heat, the wax would fall off, and the cracks corroded by acid would be revealed. Recently, the production methods of B-grade products have become more and more sophisticated, and the flaws are almost invisible to the naked eye, which makes identification quite difficult. The new method of making B-grade jade is: first of all, in terms of material selection, you should choose varieties with original green color but yellow, gray, brown and other colors as the base, and its structure is required to be not too dense. The jade piece should not be too large. It is soaked in strong acid (such as hydrochloric acid, dilute sulfuric acid, etc.), generally for 2 to 3 weeks. Observe the jade sample and find that the yellow, gray, brown and other colors are basically removed. The jade after bleaching is bright in color, the green is prominent, and the base color is obviously whitened, but this kind of jade has a cracked appearance due to acid corrosion. At this time, soak it in a weak acidic salt solution for 1 to 2 days to neutralize the acid, and then wash it with clean water. Put the cleaned jade into a drying box and dry it at a temperature not exceeding 200℃. Although its overall structure has not changed, its microstructure has been severely damaged, resulting in loose silk screens and nest structures, which reduce the strength of the jade. In order to restore its strength, it needs to be filled with epoxy resin with stronger adhesion. The filling method is: first heat the sample to below 200°C, then immerse it in epoxy resin, then take it out and dry it, so that the resin can evenly penetrate into the cracks of the jade and solidify. Finally, polish the solidified jade according to its original shape to remove the surface glue visible to the naked eye.

Understanding the production process of B-goods will help in identifying them. Usually, we can identify B-grade jadeite from the following aspects:

1. Transparency. B-grade jade is mostly translucent to slightly transparent, but its transparency decreases when placed in water and it feels like wax. Using a spotlight perspective, the surface appears to be covered with a white cover, and the internal structure is unclear. However, when looking through natural jade, its internal loofah-like network structure can be seen.

2. Gloss. B-grade jade has a dull luster and lacks the brightness and wateriness of natural jade. It looks like a plastic product.

3. Feel. When you touch B-grade jade repeatedly with your hands, it feels warm and smooth like glass, but it does not have the wet and slippery feeling of natural jade.

4. Sound. When two larger pieces of jadeite are placed against each other, the B-grade jadeite will make a hoarse sound like cracked porcelain.

5. Observe with a magnifying glass. Under a 10x magnifying glass, the surface of B-grade jade is covered with spider-web-like tiny cracks. If polishing is not in place, epoxy resin residue (milky white waxy substance) will still be visible on the surface.

There are many types of B-grade jadeite circulating in the market, and they look very similar to natural jadeite to the naked eye. It is indeed difficult to accurately distinguish them. Fortunately, it is difficult to change the process of making B-grade jadeite, which requires it to be bleached and then injected with fillers. As long as you understand its production process and master certain identification methods, you can quickly identify B-grade jadeite.

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