What is an HPHT processed diamond?
HPHT stands for "High Pressure High Temperature". When a diamond is "HPHT Processed", it has been exposed to heat in excess of 5,000˚F and pressure of 700,000 pounds per square inch to change its naturally occurring color. This process only works on rare type 2A naturally mined diamonds which are typically brownish to gray in color. Most HPHT processed diamonds turn near colorless white, but occasionally the process can yield colors in blue, pink and yellow hues.
Why purchase HPHT processed?
Since the rough type 2A diamonds are normally an undesired color, but excellent clarity, we are able to purchase these goods for an extreme discount. After we are finished with the HPHT process, the resulting diamond has a very high color grade / clarity combo. Since the rough stone was discounted so dramatically, we are able to pass that savings on to you!
The HPHT process only works on rare type 2A diamonds. Experts classify diamonds into groups to indicate slight differences in their molecular structure. Type 1 diamonds, which make up more than 98% of all the diamonds mined in the world, are identified as stones that contain a natural nitrogen impurity. Type 2A diamonds, which are far rarer, have a perfect molecular structure and very low nitrogen content. Because of this perfect molecular structure, when exposed to the proper conditions, the color of type 2A diamonds can improve dramatically. In some cases, the proper conditions have occurred in Mother Nature, creating world renowned type 2A diamonds such as the Cullinan and Koh-i-Noor. We strive to find type 2A diamonds that have not been exposed naturally to the correct temperature and pressure required to “finish what Mother Nature started”. The end result from an HPHT processed diamond is the same as if it has been exposed to millions of years of heat and pressure under the earth's crust. Once a diamond has undergone the HPHT process, it cannot be undone or revert back to its original state.
Frequently Asked Questions
Do HPHT processed diamonds require any special care?
No. HPHT diamonds are structurally identical to non-processed diamonds. You may treat them the same way you would treat a non-processed diamond. They can be recut or re-polished, exposed to a jewelers torch and be cleaned with any chemical or process that is currently used for diamonds.
Will people know I have an HPHT processed diamond?
No. This process is undetectable without the use of gemological laboratory equipment. Neither you, nor any jeweler will be able to tell that these diamonds have been processed in any way.
Can an HPHT processed diamonds revert back to its original color?
No. Once a diamond has been "HPHT Processed" it can never revert to its previous state. Because of this fact, HPHT processed diamonds are certifiable by accredited gemological laboratories such as the GIA, which is the leading authority for the diamond industry.
Are HPHT processed diamonds artificially grown in a lab?
No. Not to be confused with "Lab Grown" HPHT diamonds, "HPHT Processed" diamonds are 100% naturally mined type II a diamonds that have only undergone exposure to extreme heat and pressure. They are not coated, filled or treated with any synthetic materials or processed.
Does the HPHT process improve the clarity of a diamond?
No. The HPHT process cannot improve the clarity of a diamond. In fact, the exact opposite can be true. In some cases the HPHT process can cause pre-existing inclusions to expand or get worse. The extreme conditions that are present during the HPHT process are so severe, that only diamonds with zero to very few inclusions can survive the treatment. For this reason, we only put the finest graded diamonds through the HPHT process. The resulting outcome is that 90% of all HPHT processed diamonds will have a near flawless clarity grade.
How does the HPHT process affect the resell value of a diamond?
An HPHT processed diamond will be worth significantly less than an untreated diamond of the same color/clarity combination, but will still increase in value at the same rate.
This means that HPHT processed diamonds can be a sound investment and a way to purchase a very high quality diamond for a fraction of the cost of its untreated counterpart.