CVD Vs HPHT – What’s the Difference?

The two primary types of diamonds are those that are mined from the earth and those that are heated or heated and polished (HPHT). Both of these methods are popular in the jewelry industry, but the process differs in the way that they are produced. HPHT is used to create fancy colored diamonds, while CVD is used for diamonds that are more affordable. There are many important characteristics to look for in diamonds, including the carat weight, color, clarity, and structural characteristics of the diamond. These features can make the difference between an attractive diamond and an unattractive one.


When it comes to manufacturing lab-grown diamonds, you can choose between two different methods. The CVD and HPHT processes are both effective in generating high quality, flawless gems. But which method will give you the best deal?

Both procedures produce colorless diamonds with comparable clarity grades. However, there are some differences between the two.

CVD is the process of growing diamonds using a low pressure and moderate temperature. Its advantages are that they produce a diamond with a geometric shape and a uniform fluorescence.

However, it can be difficult to tell a CVD from a HPHT diamond. While the morphology of both types of diamonds is identical, the HPHT process can also produce more brownish diamonds.


When it comes to the clarity of CVD Vs HPHT, it is important to understand the differences. Generally, these two processes produce colorless diamonds and have similar grades. However, there are a few differences.

First, the color distribution feature is the main indicator. CVD diamonds are typically colorless and have minimal impurities, whereas hpht diamonds have more color and may have excess metal impurities.

The shape of the crystals also influences the growth process. In CVD diamonds, the crystals are shaped like a cube. It is also easier to see the plasma that forms to form a CVD diamond.

The HPHT process requires sophisticated equipment. It involves exposing a small diamond seed to extremely high pressures. This leads to formation of a carbon crystal around the seed. Once the diamond is formed, it is then heated to a temperature of 1500 degrees Fahrenheit.

Carat weight

There are two major methods used to produce lab-grown diamonds: the CVD (Chemical Vapour Deposition) and the HPHT (High Pressure High Temperature) methods. Each is a process designed to create flawless diamonds.

The CVD method uses lower pressure and uses smaller machines than the HPHT method. In both processes, a seed of diamond material is placed in a carbon deposit. However, in the HPHT method, the seed is exposed to extreme heat. This causes the carbon to melt. It then forms a diamond around it.

During the growth process, CVD diamonds are formed in thin layers. The CVD process can produce diamonds in just two to four weeks. But the HPHT method requires much more energy and specialized equipment.

Structural characteristics

HPHT and CVD are two different processes used to produce lab-grown diamonds. While they are similar, they are also quite different in many ways.

The HPHT process involves the growth of diamonds on a thin plate of a single diamond substrate. The diamonds are then annealed to remove optical features.

In contrast, the CVD process does not require high pressure. However, it is important to note that both procedures have their own structural characteristics.

HPHT produces colorless synthetic diamonds, while the CVD process produces brown diamonds. Natural type IIa brown diamonds are nearly transparent in the UV-visible range. A variety of factors, including temperature, catalyst, and carbon source, affect the growth process.

During the growth process, the diamond is exposed to nitrogen, which helps to trap vacancies. Nitrogen also decorates defects. As the process increases in temperature, the nitrogen-related defects become mobile.

HPHT vs mined diamonds

There are two main methods used to create diamonds. One method is called the Chemical Vapor Deposition (CVD) method and the other is called the High Pressure, High Temperature (HPHT) method. Despite the differences in the procedure, both produce flawless diamonds.

CVD diamonds are usually created using a chamber that is filled with carbon-rich gases. These gases are heated to approximately 1500 degrees Fahrenheit. The diamond seed is then placed inside of the chamber. After the diamond has been formed, a post-growth treatment is performed to help improve its color.


The high pressure, high temperature (HPHT) process uses equipment that is larger than that of the CVD method. This method was first developed to create colorless diamonds at a lower cost.


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