Can A-grade jade be identified with the naked eye? This is how even a novice can learn

The beauty of jade has been the dream of countless ladies, and the value of jade has attracted countless men to collect it. More and more people are buying jade, but many people do not know how to identify and select jade. Today, the editor will introduce to you how to identify genuine jade with the naked eye.

1. Determine the A-grade goods based on the surface reflection

For jadeite with large curved surfaces, placing the sample on a table with strong luster will cause obvious light differentiation zones to form on the surface of A-grade jadeite due to the reflection of the table and the light from the light source. This shows that the surface of A-grade jadeite is smooth and clean, and also shows that the surface of A-grade jadeite has a strong glass luster. B-grade products often lack this light differentiation band.

Key point: reflective area! The reflective area is a local area with strong reflections. It does not necessarily mean the difference between colored and colorless. The color difference can be reflected in the difference in color types, but the reflective area emphasizes the difference in light and dark tones of the color and the color saturation caused by the reflection. Therefore, it is easier to judge if you imagine the jade as a black and white image.

2. Determine the A-grade goods based on the surface color level

For an environment with strong light sources (such as a sunny room), if the transparency of the jade is relatively high and the quality is fine, it can often produce cold light spots on the surface. Even if the body color of the jade is warm, this color contrast is unique to A-grade jade.

People with a background in painting can easily understand this point. When a bright object with a simple color is placed in front of the painter, its color still has warm and cool tones.

Key point: cool and warm tones. Color scale refers to the degree of warmth and coldness, thickness and lightness of colors.

In A-grade jadeite, strong areas of warm and cool reflective tones that do not coexist in the same area can often be observed on its surface. In particular, the cool tones that represent strong reflections are often not present in B-grade jadeite.

3. Determine the A-grade goods based on the internal package

Jade inclusions are generally of the following types: brown inclusions; black oxides; blue-green inclusions; white cotton-like substances.

Leather is the most common infected material. Products that retain the leather are generally A-grade products, but be careful of fake leather. Genuine leather: The skin and flesh are clear, with strong color difference. The leather can have different color forms, but the boundary between the skin and flesh is clear.

Natural leather is surrounded from the outside to the inside, while dyed or fake leather spreads from point to surface. The transition of the skin and flesh of A-grade goods is sudden and sharp, and the color changes are obvious, such as brown-red suddenly changing into white, or gray-white suddenly changing to blue-green.

For other brown infection substances, current technology can make the brown color of B+C accurately resemble its natural form in morphology like a scalpel, so the significance of identification is not very great, but some other evidence can be sought: fine carving - important reference evidence; color matching - important reference evidence.

Black oxides are mainly chromite, magnetite and zirconia. They are opaque black with metallic luster, and are distributed in dotted (fly wings) and spotted forms. They often coexist with bright green or gray, reflecting the role of metal ions in the color of jadeite.

If the black inclusion has a weak reflective metallic luster, it must be a Grade A product. If it looks like a fly wing, you need to be vigilant because B+C can also simulate a fly wing. The blue-green infection is very similar to dyeing, and the surface characteristics are similar to those of B goods. Often accompanied by brown infestation, often coarse ice particles.

Distinguish dirty and dyed jadeite with large cracks. The particles have orientation, elongation and local radial shape which are not possessed by B-grade products.

The white cotton-like substance with good water head is in ball shape and often does not stick to each other. The fluff occasionally intersects but they are not at all sticky. The flocs in B-goods are often the result of glue filling in mineral particles (flocs), which creates the illusion of cotton-like inclusions. Therefore, the flocs in B-goods are often sticky, and the key is that their shapes are irregular.

4. Determine the A-grade product based on the internal glow

The significance of using surface reflection and surface color gradation to identify A and B grade jadeite has been introduced above. Reflection and color gradation are external phenomena. The glow—known in the sales industry as fluorescence (note: not luminescence) or photic glow—is an internal phenomenon. The glow of A-grade jade appears warm, while the surface reflection and color gradation appear cold; the glow of B-grade jade appears cold, while the surface reflection and color gradation appear warm - it appears warm yellow due to the aging of organic matter.

Even when observed against a blue background, you can still see the obvious yellow glow in jadeite with good water content.

Due to the diversity of jadeite varieties, even among samples with poor water head, there will be a few areas with uniform and fine texture. Therefore, glow observation has broad significance. The glow reflects the combined effects of reflection, refraction, scattering, interference and diffraction of light by tiny crystal faces and cracks in the jade structure, which is similar to the moonlight effect.

B-grade goods lack this phenomenon because of the glue's uniform effect on the structure. The effect of B-grade goods on light is more about transmission and absorption. We observed that the blue and white color in B-grade jade reflects more of the natural color of the glue and its fluorescence (the luminescence phenomenon caused by energy excitation in the gemological sense).

5. Determine the grade A product based on micro cracks

It is quite common for A-grade jadeite to have cracks between crystals (which appear as ice debris) and stress cracks (which appear as large cracks running through) due to crystallization and geological stress, especially in jadeite with poor water head.

As mentioned above, B-grade glue has a homogenizing effect on the structure, and then the internal cracks are filled. It only produces "traces of earthworms" on the surface - with the development of technology, the traces of earthworms on the surface of B-goods are becoming less and less obvious, even under a microscope, so the traditional "acid etching" evidence of B-goods has been challenged.

Except for the white ice debris, the color reflection has a clear dividing line. The area below the dividing line is bluish because the background color has a blue tone. This color affected by the background has almost no identification significance.

Look at the color of the upper part, which is the original color of jadeite. At a glance, the color is bright, but if you look closely, it has an obvious yellow tint. If you observe it through light, this phenomenon is more obvious - the glow plays a certain role.

White cracks are an important sign of A-grade goods. No internal cracks can be seen on the B-grade goods, only the "worm tracks" can be seen on the surface. Be careful with aging B-grade goods. For example, if the B-grade goods have been made for several years, especially after being exposed to the light from the counter, the glue will be obviously oxidized and cracks will appear at this time. The silky texture is like the marshmallow phenomenon and is due to dense cracks, which is evidence of A-grade products. B-grade products generally do not have this phenomenon.

It is difficult to see the internal cracks and the blockage of light and color caused by the internal cracks in B-grade jadeite that has been filled with glue. As a result, the color appears to be diffused and the boundaries are unclear (experts call this "floating" color).

The reason why A and B goods are determined by color roots and color floating is because of the cracks’ blocking effect on colored light. For example, if we drop a drop of ink on very broken ice particles, such as a compacted snowball, we often find that the color is very limited, and the color goes wherever the ink goes. This is called "the ground eats up the color" - A-grade goods. If you drop ink on the surface or corner of a transparent ice cube, you will feel that the area without ink also has color. This is called "color reflecting the base" - A or B grade jade.

There is a phenomenon of color divergence - this is common in B-grade jade, but color divergence does not necessarily mean it is a B-grade jade, because whether the color root diffuses or not is also related to the structure and particles of the jade. For example, lake green and blue emerald.

That is to say, B-grade products often have divergent colors, but those with divergent colors do not necessarily mean they are not A-grade products. A goods have two kinds of roots: tangible and intangible. When the color root is invisible, the disappearance of jadeite color will inevitably be accompanied by a drastic change in texture or large cracks. The disappearance of floating color of B-grade jadeite is often vague, and the quality does not change.

Jade players classify jewelry into different types according to their sizes: ring faces, pendants, handles, and ornaments. There is no strict boundary between the classifications. Sometimes ornaments are smaller than pendants, and sometimes ring faces are larger than pendants. Then there are the bracelets: rings and bracelets.

It is generally believed that the handle is a three-dimensional sculpture, nearly egg-shaped, while the ornament is larger than the handle. In this case, there are no B-grade handles, only A-grade ornaments. The production process of B-grade jadeite was mentioned above. So when you see something that is extended on a flat surface and is not a decoration, or is not the size of a handle, you should think of “sheet material” - a necessary condition for B-grade jadeite.

Bracelets and rings are all products made of sheet materials. Especially bracelets, you should always remember that they are made from sheet materials.

If the flakes are merely warning evidence, some types of carvings can be elevated to diagnostic evidence, such as large ornaments, handles with a three-dimensional radial size of more than 3 cm, and other carvings.

In addition, jadeite, which is known as high B in the industry, often appears in the form of round, oval plain or nostalgic (peace buckle) shapes, is well polished, and has almost no evidence of acid etching marks.

However, structural damage and the presence of glue lead to a decrease in hardness, and the huge difference in hardness between glue and mineral particles means that even things with high B are inherently defective in terms of firmness, so it is impossible for them to appear in certain shapes. For example, some finely crafted products can be considered A-grade goods.

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