Grade A jadeite: natural jadeite that has not undergone any artificial processing other than cutting and polishing to destroy the jadeite structure. Grade B jadeite: Jadeite that has been acid-washed and bleached to remove impurities and then injected with organic substances, such as glue and wax injection after acid washing. C-grade jadeite: jadeite that has been artificially colored. B+C grade jadeite: Jadeite that has been acid washed, bleached, filled with color, and then injected with glue D-grade jade: It is not jadeite, but a jadeite sold as jadeite. How to Identify A, B and C Grade Jadeite 1. Through the surface structure of jadeite The structure is compact and fine, flat and smooth, with a "emerald green" quality. There are three main characteristics: "floc", "orange peel phenomenon" and "fly wings". 1) "Flocculation" Also called cotton wool, when jade is exposed to light, some cotton-like substances will appear inside or on the surface of jade. 2) “Orange peel phenomenon” It refers to when jade is magnified and viewed under the reflection of light, you can see features similar to orange peel, with depressions and projections of varying sizes and directions. The "orange peel effect" on the surface of A-grade jade is due to the different hardness of different mineral crystals inside the jade. The softer particles will be worn away to form a concave shape. 3) “Fly Wings” It refers to the bright white reflective features of the jade surface that appear like fly wings when exposed to light. It is also one of the evidences for identifying A-grade jade. The surface of B and B+C jadeite: After being pickled and bleached with strong acid, no impurities are visible. After pickling, the structure is loose and not dense, and the jadeite texture cannot be seen. There are three main characteristics: "acid etching reticulation", "resin-filled dissolution pits" and "bubbles". 1) “Acid Etching Texture” The acid-etched reticulation is caused by the relatively low hardness of the glue filling between the mineral particles of B-grade jadeite. During cutting and polishing, the low-hardness glue is easily polished off to form concave grooves that resemble cracks in dry soil and are distributed in a network-like pattern. They are also called tortoise cracks. 2) “Glue-filled dissolution pits” After chemical injection of glue, if you magnify the surface of B-grade jadeite, you will see glue-filled corrosion pits. 3) “Bubbles” When the glue-filled dissolution pits are relatively large and obvious, sometimes you can even see "bubbles" in the glue. The bubbles are generally jade that has been treated with wax injection. According to national standards, it is also B-grade jade in commercial terms. If we distinguish A, B and C grade jadeite simply by looking at its surface, the characteristics of A grade jadeite are "flocculation", "orange peel phenomenon" and "fly wings", while B grade jadeite has no impurities, "acid-etched net patterns", "resin-filled corrosion pits" and "bubbles". Some newcomers to the industry may confuse the "orange peel phenomenon" of A-grade jade with the "acid etching network pattern" and "glue-filled corrosion pits" of B-grade jade. The author makes a comparison chart here. 2. Differentiate between A, B and C jadeite by its color The authenticity of jadeite can be distinguished mainly from two aspects: color tone and color root. 1) Look at the color tone Grade A jadeite: natural color, high gloss, obvious jadeite, fine texture, most of which have impurities, such as small rust spots, small black spots and other unevenly distributed colors. Grade B jade: dull color, loose structure, low gloss, and no visible jade texture. After rinsing and gluing, impurities are dissolved and there will be no yellow or dirty bottom, but the light green and pink lotus bottom colors will still exist, which is relatively clean. B+C grade jadeite: The color is evil and dull, the color roots are diffuse, the color is floating, and the jadeite nature is not visible. As shown in the picture above. For the same piece of material, the one on the left is Grade A, the one in the middle is Grade B after acid washing and bleaching, and the one on the right is Grade B after glue injection. The A-grade jade has an obviously yellow base and is dirty. After being injected with glue, the water head is obviously much better, and there are no impurities or grayish-yellow components. If you look closely at the light green part, you can also find similar characteristics. The green appears particularly bright and pure, without any interference from yellow and gray tones. However, there are a small number of B-grade jadeite that were not thoroughly pickled or used with resin glue with a yellow tint, and this feature cannot be seen. 2) Look at the color root What is the color root of jadeite? When light propagates in natural A-grade jadeite, it will be obviously blocked by the boundaries between jadeite grains or micro-cracks, and may appear in the form of filaments, bands, clouds, dots, clusters, sheets, etc., as shown in the figure below. B and B+C jadeite are soaked in strong acid and injected with color. The color roots of the jadeite are diffused and dispersed. The color changes from dark to light and from presence to absence. The transition is so great that it is almost impossible to tell where the color starts. This is called color root diffusion, or some people call it color floating. This is because the glue in B-grade jadeite fills the cracks that block the color. Light can easily pass between the jadeite particles without reflection from the crack surface, as shown in the following figure: However, today's dyeing technology is too mature and can achieve dot coloring, so seeing whether the color root is floating is only an auxiliary judgment. It must be comprehensively identified in combination with other characteristics. The picture below is a B+C grade bracelet that imitates the color root of A grade. 3. Distinguish real and fake jade by sound and weight sound: 1) Hang the ornaments with thin wires 2) Use agate or grade A jadeite to gently bump it. A-grade jadeite will emit a very melodious, clear and echoing sound. The crisper the sound, the more pleasant it is, and it has a metallic feel. B-grade jadeite will emit a dull, unclear and non-pleasant sound. Weight: Mainly used to distinguish D-grade jade. Jadeite is a kind of hard jade with a higher density, and is relatively heavier than other jades. Summary: To initially identify the authenticity of jadeite, it is necessary to judge based on the complementary factors of jadeite's structure, jadeite properties, surface condition, color, color roots, etc. It is not advisable to judge from only one aspect. Accurate judgment of AB goods also needs to be based on long-term practice. At first glance, this is a colorless ice-type Guanyin. Upon closer inspection, it is found that although it has a clean base, it emits a faint yellow light inside, which is actually evidence of A-grade jadeite. Upon further observation, some small cotton dots were found inside, and upon closer magnification, the "fly wings" mentioned above were also seen. So judging from the picture alone, this is an A-grade jadeite. Of course, this colorless jade is very similar to quartzite. The easiest way for experienced people to distinguish it is by weight or the refractive index of light. Jade is heavier than other jades. From the structure of jadeite, it is delicate and compact, with obvious "jade properties" on the surface. In terms of color, the ring has a clear color dividing line and a lot of white residue. There is no acid washing or color root diffusion phenomenon. Moreover, the color is bright. If you look closely, you can also see a yellow tone, which is the yellow sun green or onion heart green of jadeite. Judging from the pictures alone, it can be judged to be A-grade goods. Friends who are not familiar with the color of jade can also follow us and check out the article "Compendium of Jade Colors". At first glance, the color of this pair of earrings is neither green nor blue, and the texture is very uniform. But experienced people don't need to look at the jadeite structure, they can tell it's not jadeite just from the glossiness and color. You can compare it with the rings above. The refractive index of light for this pair of earrings is obviously not high, and the color and gloss appear dull. This is Australian jade. We don't say that the color of the bracelet is floating or that the base is white. What we want to say here is that the whole thing is evenly distributed, without any streaks or imperfections. As the saying goes, nine out of ten stones have cracks, but because of the glue filling, the so-called cracks cannot be seen with the naked eye. Even if you find a network pattern corroded by acid under a magnifying glass, when you look at it with the naked eye, there is no sign that the network pattern extends into the interior of the jade, which is evidence of B-grade jade. If it is an A-grade product, due to the influence of the crack width (lower than the resolution of the human eye), people often first see the reflective surface of the internal crack (white) rather than the crack grooves on the surface. Don’t ever think that the ones with green dots and blue flowers are A-grade jade. In fact, we have already talked about how the B+C color was achieved. Objectively speaking, the surgical knife-like dyeing technology has become quite mature. Therefore, the traditional view is that the color of B is floating and the color root is diffused, but current technology can break this tradition. The obvious boundary between color and ground is generally evidence of A-grade jade, and it cannot be completely ruled out that it is B. These bracelets are all B, or to be more precise, B+C. Authoritative jewelry testing agency: Guangdong Jewelry, Jade and Precious Metals Testing Center (GTC) issued an authoritative certificate If you have any doubts about the jadeite in your hand, you can go to the national inspection, provincial inspection and other authoritative organizations to issue a jadeite certificate, which is highly credible. fcgc66 fcpf18 |
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