The difference between HPHT treated natural & lab-grown diamonds.

There is a wide variety of diamonds from natural and lab-grown to treated diamonds. Since their prices vary a great deal too, it is necessary for someone buying a diamond to understand the differences. 


A What is an HPHT lab-grown diamond?

Natural diamonds were formed billions of years ago around 150 km below the surface of the earth. The HPHT process creates similar conditions required in the earth for diamond growth. HPHT stands for high pressure and high temperature. It is one of the main methods used to form diamonds.

A diamond seed is placed in a large press producing high pressures of above 870,000 pounds per square inch at very high temperatures (1300-1600 °C). A high purity carbon source is dissolved in the metallic flux made molten during the process. The carbon atoms then crystallize around the seed crystal, forming a lab-grown diamond. Later, the lab-grown crystal is cut and polished, ready to be set in jewelry.

What are HPHT treated natural diamonds? 

Scientists in the 1990s began experimenting in the same HPHT equipment for ways to change diamond color. This led to high pressure, high temperature color treatment. So, HPHT treated diamonds are real, natural mined diamonds that undergo the HPHT process to enhance their color.

The treatment permanently turns brownish diamonds into colorless stones. It can also create fancy colored diamonds from yellowish looking diamonds. Since the original color was brownish or yellowish, the resulting treated diamonds are still less expensive than their untreated counterparts. An HPHT treated diamond is a great option because it is a natural diamond that comes at a fraction of the cost.

How To Tell If A Diamond Is Lab-grown Or Has Been HPHT Treated?

Due to its low-cost operations, HPHT is the most common method used on a commercial basis. Sellers are required to tell you if your diamond is HPHT lab-grown or HPHT treated. Some jewelers sell lab-grown diamonds that also undergo HPHT treatment, which is why we always stress on being aware of what you’re buying. Trained gemologists can detect HPHT grown and treated diamonds using advanced scientific instruments. Labs like GIA include any diamond treatment in their reports. That is why, it is best to send the diamond to a reputed laboratory for grading to be sure.

At ILA, we have a large collection of certified diamonds showing you the best options at the best prices. For the first time, you get to check and compare the prices of identical ethically mined diamonds alongside lab-grown diamonds, so you can see the price differences and savings. 

Learn more about how our intelligent AI helps find you the perfect diamond.