Do you know how to identify A, B and C grade jadeite?

Many books and articles have discussed how to identify A, B and C grade jadeite, but some of the recommended identification methods lack operability, such as infrared spectroscopy and laser Raman spectroscopy. As an ordinary collector, these instruments and equipment are unaffordable, and even if you can afford them, they are difficult to obtain. The identification based on feeling of some "experts" is even more difficult for beginners to master. For example, the green color of B-grade jade has a feeling of being dissolved and floating; after being injected with glue, the green color of B-grade jade is weakened, and it appears hazy and unclear. This feeling is an experience gained by a professional after years of identification of A and B goods. It is not easy for ordinary collectors to master it in a short period of time. The author has also been struggling to pursue and search for this feeling, but is still confused and has achieved little success.

So, for a collector who is new to this field and has only a few simple tools (40x magnifying glass, high-power flashlight, balance or diiodomethane, refractometer or monobromonaphthalene), how should he distinguish between A, B and C grade goods? The editor thinks that we should start with density first. That is to say, every time you get a piece of jade, the first thing you need to do is to measure its density. Any value lower than 3.33 should attract attention. The reason is simple. Although the density of jade is defined between 3.25 and 3.43, the texture of jade with lower density will not be very good even if it is A-grade jade. And the possibility of jade with density above 3.33 to become B-grade jade is lower. Because not all jade is suitable for being B-grade jade. Generally speaking, B-grade jade has a coarse and loose texture, poor transparency, and contains yellow-brown and black speckled substances; in addition, in terms of color, jade suitable for being made into B-grade jade must be green. But not all jadeite with green color is worth working with. Only those jadeite with better green color but low transparency and many impurities in it are worth working with. More importantly, most of the materials used to process B-grade jade are 83 jade, while the relative density of 83 jade is lower than 3.33, ranging from 3.25 to 3.31. This provides us with a reference data to correctly identify A goods and B goods. Secondly, carefully observe the surface characteristics of the jade. When observed with a 40x magnifying glass with side lighting (oblique lighting method), the surface of A-grade jade is as smooth as a mirror, with a strong glassy luster. Even some small sand holes and pits appear in the form of triangles or polygonal strips where the mineral grains meet. The sand holes and pits of B-grade jade are mostly in the form of dissolution holes, which are characterized by being round, deep, black, and having blunt edges. In addition, the surface of B-goods is covered with irregular, criss-crossing, network-like and tree-branch-like grooves, just like an aged asphalt road. Although fine lines can be seen on the surface of A-grade jade, they are the fine lines between the particles. Some A-grade jades with inferior texture may have some grooves due to poor polishing, but these grooves only appear in the parts that are difficult to polish, and there are no signs of corrosion on the edges.

The identification of A and B grade jade bracelets is generally based on listening to the sound. If there are no cracks, lift one bracelet with your fingers, pick up another bracelet or other hard object and tap gently (be sure to tap gently, using too much force will damage the bracelet and the sound may be wrong). The sound of A-grade bracelets is crisp, long and echoing, and has a metallic sound; the sound of B-grade bracelets is dull and hoarse.

It is relatively simple to identify C-grade jadeite. Usually a strong flashlight is used to illuminate it. The green of A-grade jadeite is colored at the beginning and end, with spots of transition from light to dark in the form of strips. However, under strong light, the green of C-grade jadeite is distributed in the form of thin lines around the grains or in the cracks.

In general, how do you distinguish between A-grade, B-grade and C-grade jadeite?

Grade A jadeite: refers to jadeite that has only been machined and whose color, structure, transparency, etc. remain in their natural state, i.e. natural jadeite;

B-grade jadeite: refers to low-grade jadeite that has been treated with strong acid and rinsed to remove impurities and stains, and then filled with glue or epoxy resin glue to fill the space lost by acid erosion. The jadeite that has been treated in this way will have "B-grade jadeite" or "treated jadeite" noted on the appraisal certificate.

C-grade jadeite refers to jadeite and its finished products that have been artificially treated with foreign dyes or drugs. The method is to use high temperature and high pressure to infiltrate the dye into the original colorless jade, dyeing it all or partly into emerald green or purple, etc., but its color will fade and darken over time.

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