Blue and white jade, like blue and white porcelain, is made up of a combination of two colors of jade, black jade and white jade. Its name is borrowed from the name of blue and white porcelain, black (ink is black) and white are mainly ink, and white is the base or embellishment.
The charm of blue and white jade lies in its unique "blue and white" effect. The white of the base color and the black of the ink blend with each other, giving people a sense of calm and mystery.
The formation of blue and white jade is formed by the staining of white or green jade with the mineral graphite, and the same is true of black jade. According to industry standards, generally the black part content of more than 30% can be called black jade, and less than 30% is called blue and white jade.
The characteristics of blue and white material are good oiliness and high hardness. According to the content of graphite inclusions, blue and white materials can be divided into two types: point ink and polyink.
Spotting ink refers to the obvious specific distribution between the graphite inclusions, which appear to be black spots and do not clump together. Ink accumulation refers to the relatively concentrated distribution of ink dots and aggregation together. Among them, the black and white blue and white material has the highest value.
There are two main types of blue and white materials: seed blue and white and mountain blue and white. The seed blue and white is produced in the Karakash River valley in Xinjiang, and the mountain blue and white is produced in Pishan County, Yutian County and Yecheng in Golmud, Qinghai. Although the jade composition of the two is exactly the same, both belong to the category of Hetian jade, but there are still certain differences in the market, and the seed material blue and white is more expensive than the mountain material blue and white.
In addition to the above-mentioned production areas, there are also different kinds of blue and white materials such as Russian blue and white materials from Ulan-Ushi De City in Russia, flint star materials in Xiuyu, and Qinghai Yanzi in Golmud City, Qinghai Province.
If you observe with the naked eye or with a magnifying glass, you can find that the ink color of the blue and white of the mountain material is densely composed of dotted ink dots, and it will be mixed with some relatively "silver sand" material (shiny fine sand spots), and this "silver sand" substance is common in the blue and white of the mountain material, so once you find this kind of sand spot, you can be sure that it is blue and white mountain material.
In addition, the oiliness of the seed blue and white is better, the material quality is delicate, generally more distinct, and the border is clear, while the black and white distribution boundary of the mountain blue and white is blurred, and the material quality is slightly loose and slightly dry compared with the seed blue and white. If the mountain blue and white is artificially imitated into the seed blue and white through the roller, the color of its skin part is additive, unnatural, and not as oily as the skin part of the seed blue and white.
The main characteristics of the blue and white material of Ulan Ushi de City in Russia are similar to those of Hetian blue and white materials, which are also ink gathering, black and white, but slightly inferior in oiliness and delicacy, and appear relatively dry.
The blue and white in Xiuyu is also the flint star material!The basic characteristic of flint star material is that it is white and transparent overall, with black cotton hidden in the middle. The bracelet is very beautiful, because of the unique color, just like the Chinese ink painting, so it is also called ink jade.
The origin of Qinghai tobacco green material is in the area of Golmud City, Qinghai Province, and it is one of the varieties of Qinghai material. This kind of material is mainly gray-purple and gray-pink with green meat or white meat, because the ink part of most of the material is similar to the green smoke produced by combustion, so it is named tobacco green material.
In the industry, this kind of material is also called black edge material, black edge material from the appearance of the shape of the blue and white mountain material of Yecheng, the difference is that the smoke green material will not be mixed with silver sand.
How to choose blue and white materials: First of all, the jade quality of the jade material is very delicate, and the delicacy should be put in the first place. Secondly, if the ink is white jade, the value is high. Again, the value of poly ink blue and white, that is, ink jade, is very high. Finally, the blue and white with skin color adds a lot of points to the value.