Red jade is called ruby for short. Ruby can be roughly divided into three categories:

First, Hotan local ruby:

Hetian primary ruby is the red color of jade when geological structure changes, and when hot rock liquid condenses into jade ore, it is doped with trace iron.

The red color of primary rubies varies from brown to pink, because it contains a lot of iron. What's important is that the red color of the original ruby is consistent from the inside out, regardless of the color depth. The colors are brownish red, pink and meat red.

Second, Hotan secondary ruby:

Hetian secondary ruby is Hetian white jade and sapphire, which is a red jade formed by the infiltration of external iron or other red factors during the formation of seed jade. Color is a gradual change from the outside to the inside, from deep to light; The core of seed material is sapphire or white jade. (Above, the brushing in Han Dynasty is).

Third, Hotan Red Seed Jade:

Hotan red-skinned seed jade is a kind of seed jade fished out of Hotan jade Longkash River, with different skin colors. Seed jade with red skin shell is also called ruby. Of course, this is only the cognition of some collectors today.

When cutting jade, modern craftsmen consciously carved the ruby skin into various patterns or images, which is the clever carving of ruby. The ancients did not think that Hetian red-skinned seed jade was ruby. Because, in the dynasties before the late Qing Dynasty, jade articles were cut without jade skin.

Extended data:

The quality of jadeite is generally judged from five aspects: texture, hardness, transparency, specific gravity and color. The texture of jade refers to the delicate and moist degree of jade.

One of the differences between jade and stone is that jade is delicate, moist and hard, translucent and glossy as fat; Stone, on the other hand, is rough and dry, lacking luster and opaque. Hardness refers to the ability of jade to resist external forces (such as pressing, engraving and grinding). The higher the hardness, the more difficult it is to process and the better the quality of jade.

Although the hardness index of jade can be known by detecting its internal crystal structure with instruments, the method of scraping hardness is generally used in operation. The hardness of common jade in China is between 4 and 6 degrees, which is higher than copper and lower than glass. In other words, jade may not be able to carve marks on glass.

Baidu Encyclopedia _ Hongyu

Baidu Encyclopedia _ Jade