How to identify B-grade jadeite within 10 seconds?

Remove impurities that affect the color and transparency of jade, fill and cover up the cracks in jade to reduce the brittleness of jade in order to increase the beauty of jade, increase the selling price and obtain high profits.

Identification of B-grade Jadeite

1. Acid etching

The "orange peel effect" is that when A-grade jade is observed through reflected light, it will have multiple bumps and depressions of different sizes and directions, similar to those of orange peel.

The "orange peel effect" is more prominent only in A-grade jadeite, and the boundary between the convex and concave gradually transitions smoothly, while the convex and concave between B-grade jadeite will not transition smoothly, but there is a crack separating them, which is called "acid etching pattern."

2. Color changes

Grade A jade has natural color and layered texture. The color of B-grade jadeite is formed after the original color is removed, and it is bright yellowish. Because the structure of jade is destroyed and its internal optical properties have changed, the color distribution of B-grade jade has no sense of hierarchy and appears to be a uniform color.

3. Observe the gloss of the surface

Because B-grade jade is filled with epoxy resin, it will oxidize after being in contact with air for a long time. It is especially easy to weather and turn yellow in a high temperature environment. Therefore, when observing B-grade jade, you can see some faint yellow luster on the surface. In addition, the luster of the surface will deteriorate due to weathering, but it can no longer be polished to restore the luster; A-grade jade can be re-polished to restore its luster.

4. Knocking sound

If you tap an A-grade jade bracelet gently with an agate stick or coin next to your ear, you can hear a pleasant sound. The sound of B-grade jade will be duller, but the texture of some A-grade bracelets is poor, so the sound will be duller when tapped. A small number of B-grade bracelets have been soaked for a short time and are filled with epoxy resin, so the sound will be pleasanter, so you must be very careful.

5. Specific gravity liquid

The B-grade jade that has been filled with epoxy resin will have a lower specific gravity due to the resin component. Therefore, we can put the jade into diiodomethane specific gravity liquid. The A-grade jade will sink to the bottom of the specific gravity liquid. After measurement, the specific gravity of the B-grade jade egg-shaped surface is usually between 2.93 and 3.21, and it will float on the specific gravity liquid.

6. Ultraviolet fluorescence reaction

Natural jade usually has no fluorescent reaction under ultraviolet fluorescent light; B-grade jade, on the other hand, will have a stronger blue-white fluorescent reaction. Factors affecting this include the type of resin used for filling. In addition, some wax-immersion jade will also have a weak to medium blue-white light reaction.

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