The first characteristic is the transmittance of jadeite.
The transmittance of jadeite is the depth at which light can penetrate jadeite. Part of the light will be reflected from the surface of jadeite, and part of the light will be transmitted from the inside of jadeite, and the light transmittance of different jadeites is also different.
If the jade passes through more light, its transparency will be better, which will make the jade look very crystal clear and have the feeling of "green water is about to drip".
According to the light transmittance of jadeite, the light transmittance of jadeite can be divided into four grades: transparent, sub-transparent, slightly transparent and opaque.
Representative varieties are: glass seed, ice seed, waxy seed and bean seed.
The main factors affecting the transparency of jadeite are: the depth of jadeite itself will affect the transparency, and the darker the color, the worse the transparency; The thickness of jadeite affects the transparency. The thinner the jadeite, the better the transparency.
The second feature is the texture of jade.
The texture of jadeite is an important index to measure the quality of jadeite. Because jadeite is a collection of various minerals, the finer it looks, the better, and the fewer stones, spots and cracks, the better.
The fineness and roughness of jadeite texture are determined by the particle size. The larger the particles, the rougher the texture, showing translucent to opaque, while the smaller the particles, the finer the texture, showing transparent to translucent.
According to the particle size, the texture can be divided into dense, fine, medium and rough grades. The granularity of jadeite directly affects the quality of jadeite texture. Generally speaking, jadeite with fine grain structure has soft texture, good water head and good polishing degree.
The third characteristic is the purity of jadeite.
The purity of jadeite refers to the degree of internal defects of jadeite, that is, other mineral inclusions (defects) and cracks. Jade, like other precious stones, purity is a major factor in value evaluation.
Jade has two main defects: white and black. Black defects, some of which appear as dots, are called black spots, and some become filiform and banded, which are called black silk and black belt. Mainly black minerals, mostly hornblende, and black spots mostly appear in darker jadeite. White defects, mainly granular and massive, are generally called "stone flowers" and "blisters", mainly albite minerals or aggregates. Defects have a great influence on the quality evaluation of high-grade gem-grade jadeite. According to ingenious color arrangement, middle and low-grade jade carving materials can be made into exquisite jade carving crafts.
The existence of cracks has a great influence on the quality of jadeite. There are two kinds of cracks in jadeite: one is caused by external impact, and the other is intergranular crack. Cracks caused by external impact have a great influence on quality, and intergranular crack is caused by the intersection of coarse grain boundaries.
The fourth feature is the flaw of jade.
The defects of jadeite refer to some impurity minerals, such as color and shape, which will affect the value of jadeite, especially high-grade jadeite. To sum up, it is cotton, grain, wrinkle and crack.
Cotton is the original internal feature of jadeite, which exists in the form of small particles, circles or living clouds. Serious white cotton turns into stone flowers, which affects the beauty of jadeite. Grain is also the original internal feature of jadeite, which is caused by local differences in color or structure of jadeite, such as banded stone grain.
Among them, ochre is the internal feature of jadeite.
There are two main formation mechanisms: the first is that jadeite is composed of different grains, and when the grains are coarse, it is easy to produce large grain gaps and flash effects under the irradiation of light; The second kind is the cracks caused by the crustal movement and extrusion friction after the formation of jadeite. Due to the infiltration of hot melt materials such as magma, cracks are repaired and fine healing cracks are formed. This is a very fine crack, which can be seen and felt.
The fifth and most important feature is the color of jade.
The color of jadeite is ever-changing and colorful. Usually people call the red color of jade "Fei" and the green color "Cui".
Rich green, bright red and violet are loved by people, among which green is the most precious. Jewelry circles often judge the green color of jadeite according to ten words: "strong, yang, savage, positive, harmonious" and "light, yin, old, evil and flower".
"thick", that is, green is full, vigorous but not black; On the contrary, light green and weak color are "light".
"Yang", that is, green is bright, bright and generous; On the other hand, if the green is dark and dull, it is "yin".
"Qiao", that is, green is even and soft, which can be coordinated with "bottom" and "water"; On the other hand, if the green is unevenly distributed in spots, peaks and blocks, it is "old".
"Positive", that is, green is pure, and there are no blue, blue and other variegated colors in green; On the contrary, it is "evil".
"Harmony", that is, green is uniform, harmonious, non-flowered and non-chaotic; On the contrary, it is "flower". The order of green is: green, yellow-green, yellow-green, gray-green, gray-green.