CVD Vs HPHT Diamonds


The process of diamond growth varies. In the lab, it takes just a few weeks to grow a diamond, while in the earth, it takes millions of years. This difference in time is due to the method used to grow the diamond. HPHT is one method that uses extreme pressure to grow a diamond. The amount of pressure required to grow a diamond must change as the diamond grows larger. The same amount of pressure can be used to squeeze a small pebble, while extra pressure is required to squeeze a large rock.

CVD uses a diamond seed

CVD is a technique for manufacturing diamonds by depositing carbon-rich gas layers onto a diamond seed. High-pressure and high-temperature conditions cause the gas to become ionized. The ions break down chemical bonds, releasing pieces of carbon onto the diamond seed and causing the diamond to grow. This process produces Type IIA diamonds, which are rare among naturally occurring diamonds. These diamonds lack nitrogen impurities and are chemically pure. Another benefit of CVD is that the diamond is not magnetic.

In addition to being environmentally friendly, cvd vs hpht is also inexpensive. It can cost 30 to 50 percent less than a mined diamond. Additionally, it does not fund conflict and leaves almost no mineral waste. This makes CVD diamonds a good alternative to natural diamonds.

HPHT uses pressure

HPHT is a laboratory process that uses high temperatures and pressure to grow a diamond. The process is very similar to the process used to grow natural diamonds. The carbon molecules are exposed to extremely high temperatures. The result is a diamond with a signature crystalline structure. HPHT diamonds cost about 30 percent less than natural diamonds.

HPHT starts with a small natural diamond seed that is placed inside a special carbon disc called a wafer. The seed is then placed into a large HPHT chamber that uses pressure plates. The temperature inside the chamber is constantly around 2,200 degrees Fahrenheit, and the pressure is over 1.5 million pounds per square inch. As the pressure builds, the catalysts inside the growth chamber react with the heat and change from a solid to molten state.

Type IIb diamonds are rare

Type IIb diamonds are very rare in nature, and constitute about 1% of diamonds. They are characterized by a relatively low level of nitrogen impurity. They also have distinctive infrared absorption spectrum, increasing in intensity towards the red part of the visible spectrum. They tend to be large and irregular, and were formed under extremely high pressure for longer periods of time.

Type IIb diamonds are uncommon in  CVD Vs HPHT synthetics. This may be due to uneven defect incorporation throughout the internal growth sectors of HPHT synthetics. In addition, boron and isolated nitrogen concentrations are not uniform throughout the stone. These differences are reflected by IR absorption spectroscopy of faceted and cut diamonds, which sample most of the diamond’s volume.

Natural diamonds

Natural diamonds are incredibly beautiful, but they also have a yellow hue. This is caused by the presence of nitrogen in the diamond’s structure, which changes how light enters the stone. Orange diamonds are also colored this way. These diamonds fall on the colorless scale between D and Z, with D being the least yellow and Z being the most colorless.

If you’re looking for a diamond with a yellow hue, you can find it in diamonds from Zimbabwe or Brazil. The yellow hue is not uncommon, and it’s not the end of the world. Most diamonds are white to light yellow, but some may also have a yellow hue.

Memorial diamonds

Memorial diamonds are made from carbon elements extracted from a person’s ashes, hair, or other remains. To create a memorial diamond, the carbon must be processed to high purity. The process begins in a lab, where special instruments remove the carbon. This extraction process is crucial for the production of a memorial diamond, and it directly impacts the color of the finished stone. There are a few differences between memorial diamonds and other diamonds.


The process for making memorial diamonds is similar to the creation of a synthetic diamond. A carbon ash is super-heated to 5,000 degrees, graphite is added, and massive pressure is applied to the ashes. Once this process is completed, a diamond crystal forms. Like a regular diamond, memorial diamonds are cut and polished.

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