Mainly through high temperature and high pressure method and chemical vapor deposition method. The technology of high temperature and high pressure method is very mature and has formed an industry. The domestic output is extremely high, ranking first in the world. Chemical vapor deposition still mainly exists in the laboratory.

Because of its high refractive index, diamonds shine in the light and become ladies' favorite gems. Huge beautiful diamonds may be priceless. Diamonds with dark colors are more expensive. At present, the most expensive colored diamond is aquamarine diamond with a slight blue color. Diamonds are divided into type I and type II, mainly depending on whether they contain N elements: type I contains N elements; Type II does not include. The blue diamond is type B, which is a semiconductor.

Extended data

Diamonds are generally graded according to degrees. The clarity grade is divided into five major grades and ten minor grades. From high to low are LC, WS 1- 2, VS 1-2, S 1 1-2. P 1-3, as follows:

LC: flawless, even the diamond grading master can't observe the internal defects of the diamond under the 10 times jewelry magnifying glass, which belongs to the top diamond clarity.

WS: Very small defect level. Although experienced masters can find tiny impurities in diamonds under the magnifying glass of 10 times, it is very difficult.

VS: minor defect level. The impurities in this diamond are also very small. Different from WS, an experienced grader can easily find impurities with a jewelry magnifying glass of 10 times, with less difficulty.

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