Jade Popularization: Identification of B-Grade Jade

Today we will learn how to identify B-grade jadeite. However, since there are many identification methods and in order to avoid tiring everyone, we will explain them to you over two days.

Acid etching marks: The "orange peel effect" is that when the A-grade jadeite is observed through reflected light, there will be multiple raised and depressed features of different sizes and directions similar to orange peel. The "orange peel effect" is only prominent in A-grade goods, and the boundary between the ridges and dents is gradually and smoothly transitioned; in B-grade goods, the ridges and dents are not smoothly transitioned, but separated by a crack, like a spider web-like crack pattern, which is called "acid etching pattern". This sounds simple, but actual observation requires considerable experience, and it is easy to make wrong judgments if you are not careful.

Color change: The appearance of B-grade jadeite has a sharp contrast between green and white, with absolutely no yellow, gray, brown or other impurities. Only green, purple and black parts are retained, and some impurity vacancies have been filled and replaced by epoxy resin. The eroded vacancies appear particularly transparent or whitened. B-grade jadeite has the characteristics of "irregular color and shape", "floating color without roots" and "inconsistent quality". Abnormal color and shape means that the color of jade is too bright and the base color is too clean. Floating color without roots means that the boundary between green and the base color is blurred, and the color feels like it is floating on top; inconsistent quality means that the grains are obviously coarse, but the water head is good and clean, which violates the laws of natural jade.

Observe the surface gloss: Because B-grade jade is filled with resin, it will oxidize after being in contact with air for a long time. Especially when working in a high-temperature environment, it is more likely to weather and turn yellow. Therefore, B-grade jadeite can be seen to have some faint yellow luster on its surface. Additionally, weathered surfaces lose gloss and cannot be polished back to their original luster. Grade A jadeite can regain its original luster by simply re-polishing.

Tap and listen to the sound: Use an agate stick or coin to place the A-grade jadeite bracelet near your ear and gently tap it, you can hear a crisp and pleasant sound. B-grade jadeite has cracks filled with resin, so the sound will become muffled and not crisp enough. One thing to note here is that the bracelet needs to be tied with a thin string and cannot be held by hand. In fact, this method can only be auxiliary. After all, some A-grade bracelets have poor texture and loose particles, which can also cause a low sound. Some B-grade bracelets may have crisp sounds because they have been soaked in acid for a short time or have only been partially filled with resin. It may be difficult to distinguish the sound at first, so you must be very careful.

Specific gravity liquid: B-grade jadeite that has been acid-washed and filled with resin will have a lower specific gravity because of the resin component. Therefore, we can put the jadeite into the specific gravity liquid of diiodomethane. The specific gravity of A-grade jadeite is greater than the "specific gravity liquid", so A-grade jadeite will sink. But B-grade jadeite will float. This method is relatively reliable and has a 90% credibility. However, it should be noted that the "specific gravity liquid" is highly toxic. It is best to hold your breath for a few seconds when observing it. The operation area should be well ventilated, and wash your hands immediately after use.

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