Jade Knowledge Lecture: How to distinguish B-grade and C-grade jade?

With the continuous development of the times, the production technology of jade is becoming more and more sophisticated, and the price is rising rapidly. In this way, some businessmen will process the imperfect and flawed jade in order to obtain more profits. Such jade is called B and C jade in the market. So how do you tell them apart?

First of all, there are B-grade jadeite. Its production technology is becoming more and more advanced. Currently, there is a kind of high-end B-grade jadeite that is made of nano-grade filling materials, and its gloss and transparency are enough to be mistaken for the real thing. Therefore, it is becoming increasingly difficult for players to distinguish between natural jade and processed jade. This shows that it is very important for players to identify jade. So what are the characteristics of B-grade jade?

Judging from the glossiness, B-grade jadeite is filled with resin before being polished, so the gloss spots of resin can still be seen in the filled pits of B-grade jadeite, and the overall gloss is a mixture of resin gloss and glass gloss. From the color point of view, the color distribution of B-grade jadeite has no sense of hierarchy and looks chaotic overall.

From a structural point of view, the raw materials for making B-grade jade are generally jade that contains more impurities and has a loose structure. When soaked and corroded by strong acids and alkalis, some substances are brought out, and dissolution will occur on the surface and inside along the mineral crystals. Interconnected cracks and surface water channels will appear inside, and the internal cracks are often jagged tensile cracks.

Under transmitted light conditions, the criss-crossing cracks inside are visible, which seriously affect the permeability. Under reflective conditions, the dissolution pits or reticulations on the surface are clearly visible, and the original glass luster of the jade is lost.

B-grade jadeite is usually filled with colloid, so the colloid will leave some bubbles on the surface or in the cracks. Moreover, B-grade jade looks purer than natural jade, and even the impurities cannot be seen with the naked eye.

In terms of fluorescence, B-grade jadeite has a uniform, medium yellow-green and blue-green fluorescence. From the perspective of thermal reaction, B-grade jadeite will carbonize when heated to 200-300℃, while natural jadeite will not melt below 800℃. Moreover, in theory, the density of B-grade jade is slightly lighter than that of A-grade jade.

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