The black leather in the Russian material was originally called “grey leather”. Its output form is different from that of Russian. Its outer skin is gray, it has a lime-like texture, it is not tight and loose, and its appearance has many corners and is in an irregular state. The thickness of the gray cortex varies from 1mm to 10mm. Below this gray earthy outer skin is grayish black jade, and then down is white jade, usually white to blue.

What is "black leather"?

Black leather on the market, specifically refers to the black leather of Russian materials. Because the dark minerals such as iron and manganese are infiltrated into the jade, especially in places where the jade is loose or cracked, it is slowly deposited, and finally the darker skin is formed, which forms the so-called "black." Leather".

The color is mainly black, and almost no other colors are seen. Xinjiang Hetian jade, there is almost no pure black skin seed, usually black and yellow, or black and red together. Black leather, feels more dry; and Hetian black skin seed, strong oily feeling.

In Qinghai and Russian materials, white or black leather is occasionally visible. Although the Xinjiang Hetian jade seed material also has some darker skin color, the black leather material is considered to be one of the characteristics of the Qinghai material and the Russian material.

Why is it called black leather?

At the time of jade mining, after the artificially removing the outer layer of lime soil, the jade reveals the black jade surface inside, which is mistaken for the black leather color of jade. In fact, this layer of black is a black jade surface rather than the outer skin of jade. The outermost gray soil layer is loose, the shape is very irregular, and the edges and corners are obvious.

In general, most of the Hetian jade black skin is often found in the cracks and is often gully on the surface of the raw material. Of course, some of the black skin parts after cutting can also be flat. After polishing, due to structural reasons, Hetian jade often presents a characteristic orange peel phenomenon. This orange peel pattern can be recognized by the naked eye in the strong reflection spot. Whether it is the skin of the seed material or the skin of Qinghai and Russian materials, this orange peel pattern is also common.

The black leather has a relatively close jade, some of which can be seen as mineral granules, but also some black leather. The jade is very fine and fine. It can be said that black leather is a very good one in Russian. The meat is very greasy, and the white flesh is interspersed with black jade on the outside and in the middle. The resources of black leather mining are also very tight, and they are relatively precious jade materials, and the price is climbing.

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