HPHT Vs CVD Diamonds

When it comes to choosing a diamond, you need to know the differences between hpht diamonds and cvd diamonds. You should know that they are cheaper than each other and have different growth directions. In addition, you should be aware that these diamonds are not as desirable as those created using CVD.

Cheaper than cvd diamonds

While the two methods are very similar, there are several differences between the two. The biggest difference between HPH diamonds and CVD diamonds is the process used to produce them. The CVD process produces diamonds with higher clarity and colour, but it is less energy-intensive, making it more competitively priced.

CVD diamonds are also cheaper than HPH diamonds, but both are higher quality and more plentiful. The choice between the two will ultimately come down to your personal preferences and your budget. If you’re on a budget, it may make more sense to purchase a HPH diamond. However, if you want to have the highest quality diamond possible, you’ll need to spend a little more.

HPHT treatment

Natural diamonds, including the ones made through the CVD process, often have a brown tint that affects their color grade. However, HPHT treatment can improve the color of most natural diamonds to a higher color grade. Diamonds with low color grades may break during the hpht vs cvd process, particularly if they have a cavity or indentation.

HPH diamonds have identical chemical makeup to natural diamonds, and can be as high as 40% cheaper than their CVD counterparts. As they are created in a lab, they have less inclusions and sparkle than natural diamonds. In addition, they are more environmentally sustainable.

They have a blue nuance

One of the biggest debates in the diamond industry is whether HPHT and CVD diamonds have a blue nuance. The answer to this question depends on what you are looking for in a diamond. HPHT diamonds typically have a high level of blue nuance, while CVD diamonds are generally much less blue. The reason for this difference is that HPHT diamonds don’t exhibit strain lines and are more clear than CVD diamonds. The blue nuance is actually caused by the boron impurities that the diamonds contain.

The reason why HPHT diamonds are so blue is because they contain excess boron. When this is present, the diamond is classified as a Type IIb or Type IIa diamond. However, this is not always the case. Some lab diamonds have no blue nuance at all.

One of the differences between CVD Vs HPHT diamonds is the process used to produce them. The first is heat treatment, while the latter uses a chemical process. While some dealers are agnostic about which treatment method is better, others prefer the latter to avoid crystal strain and the presence of a blue nuance. However, both methods produce diamonds with the same high-grade color, and the difference in price is minimal.

Different growth directions

CVD and HPHT processes both produce diamonds with the same chemical composition, but these processes are different in growth directions. Although CVD grows diamonds with a higher degree of transparency, HPHT grows them with a lower level of transparency. Consequently, HPHT diamonds are not as valuable as diamonds made with CVD processes. This fact has led many diamond companies to advise their customers to avoid diamonds made with HPHT processes.

The main telltale difference between HPHT and CVD diamonds is morphology. A HPHT diamond grows in a cuboctahedron shape with 14 growth directions, while a CVD diamond grows in a cubic shape with only one growth direction. These differences are enough to distinguish them by an experienced gemologist.


The HPHT process involves the use of carbon, either a powder or graphite, combined with chemicals in a reactor chamber. The combination of carbon and chemicals in an HPHT process minimizes the cost and technological complexity of diamond growth. Typically, the HPHT process grows diamonds at temperatures between one and six GPa.

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