What is the difference between CVD and HTHP synthetic diamonds?

First, the synthesis method is different.

1. CVD diamond: microwave plasma chemical vapor deposition method; Temperature and pressure are also two key factors in the creation of crystals, by making diamonds in ceramic containers rather than underground, where water pressure provides high pressure and electricity generates high temperatures that allow the carbon to form crystals around a seed crystal made of natural diamonds with a diameter of 1 millimeter.

2. HTHP diamonds: natural diamonds are treated with high temperature and high pressure to enhance the color grade of diamonds. Generally speaking, it can be upgraded to 4-6 levels.

However, not every diamond can be treated with this technology, and it must be a type IIA diamond with a J color or higher, free of impurities, and high clarity.

Second, the characteristics are different.

1. CVD diamond: the inclusions have alloy inclusions of different forms; Color: Most synthetic diamonds are yellow, thirsty yellow (most) with hourglass bands; Natural diamonds, on the other hand, are colorless, light yellow, and other colors.

2. HTHP diamonds: Diamonds treated with HPHT may also deepen or change their color to become colored diamonds; When processed, it is not possible to ** its results. That is, it is not certain what level can be raised.

The definition of industrial diamonds and gem-quality diamonds is based on natural diamonds produced in diamond mines, and high-quality diamonds are used for diamond embryos, that is, gem-quality diamonds; Poor quality gemstones that are not good enough for use will be used for industrial purposes, that is, industrial grade diamonds.

CVD synthetic diamonds are synthesized with natural diamonds and many gases in a specific pressure and temperature environment for a long time, and synthetic diamonds, including HTHP method, CVD method, etc., are limited to the laboratory stage, and have not been used in industrial use on a large scale, nor have they been able to enter the jewelry market, because synthetic diamonds and artificially treated diamonds have unique characteristics, and these diamonds will be distinguished under the identification of professional personnel and instruments, so diamonds with certificates on the market can be considered natural diamonds.

Gem-quality diamonds, the quality is no different from natural diamonds, they cannot be distinguished by the naked eye, unless they are identified in a laboratory, and ** are not cheap.

In the past few years, the mass production of gem-level CVD diamonds, now the technology has been perfected, and there is full technical ability to produce gem-level CVD diamonds, the diamond group De Beers has officially announced the establishment of a brand to produce artificial diamonds in 18 years, ** is about one-fifth of natural diamonds, the American diamond industry is expected to account for more than 20% of the market share of artificial diamonds by 2020, and there are already artificial diamond brands in China.