Heritage of HPHT

The history of HPHT treatments dates again to 1955, when the Normal Electric powered Business first uncovered the procedure for producing diamonds in the laboratory. This led to the creation of HPHT procedure, whereby GE first created a push the place the necessary strain and temperature could be managed for the system. Just one point led to another and HPHT treatment method developed as a result of various presses like the tetrahedral, BARS and eventually the cubic press. What began as an experiment for diamond color modification in artificial diamonds has currently advanced into utilization for all-natural diamonds also.

Use of HPHT Diamond Enhancements HPHT treatment plans basically provide two needs

  • Generation of synthetic diamonds
  • Color modification in pure diamonds

Making synthetic diamonds: To attain artificial diamonds, carbon is set within a grapite capsule. A seed is then inserted into this capsule and a catalyst is additional. The diamond grows on the seed even though the catalyst enables the crystallization to take spot.

Coloration modification: Different style of diamonds react differently when exposed to HPHT solutions and a array of colors are obtained. For instance, diamonds made up of aggragated nitrogen, when uncovered to HPHT can induce it to grow to be solitary substitution nitrogen. In these types of scenarios, diamonds acquiring environmentally friendly, orange and yellow hues can be created. In diamonds wherever nitrogen is negligible, the system is generally employed to generate colorless diamonds. Therefore brownish diamonds when HPHT processed can acquire a colorless hue. A light-weight pink colour could also be attained in some cases. In situation of diamonds with negligible nitrogen and existence of boron, HPHT can alter the coloration. So brownish diamonds will eliminate the brown tone and boron will make the stone bluish in colour.

Popular presses employed for remedy

Belt presses: This was the original variety of press used for cure. Right here stress is established by the use of two substantial toughness pistons that provide equal tension in opposing instructions on a sample. A collection of rings encompass the sample in order to incorporate the pressure.

Torid push: In this process, the two pistons implement force in a solitary vertical way.

Cubic press: This works by using lots of pistons that give strain from diverse instructions. It is also recognised as a tetrahedral push.

Method of HPHT

If a client intends to give diamonds for this treatment method, the next method is utilized,

  • The stone is initial inspected by diamond gurus for cracks, fractures etcetera. Stones are also matter to chemical analysis making use of scientific devices. As soon as it is verified that the cure can be undertaken, the exact is knowledgeable to the purchaser.
  • Based upon the attributes of the stone, the colour that could be received soon after remedy is deciphered and the consumer is knowledgeable about the similar.
  • Stress of about 1,000,000psi is used by inserting the stone in an interior tension medium that distributes the strain on the overall diamond similarly.
  • The inner strain medium is positioned into a heat making sleeve the place temperatures start out at 1800 levels centigrade.

Pricing of treatment options: Expense for these treatment plans differs with the measurement of the diamond. Also the complete quantity of stones provided and more services like repolishing are billed excess. Though these treatment plans are expensive,

Corporations and HPHT

Simply because HPHT is controversial, unique bodies follow diverse rules for HPHT. As per the Federal Trade fee, HPHT taken care of diamonds must be disclosed to the consumer. Typical Electric follows this norm and all diamonds that are HPHT handled are laser inscribed with the terms ‘HPHT PROCESSED’, IRRADIATED. If GIA notes diamonds to be HPHT taken care of, it also specifies them as ‘HPHT ANNEALED’ or ‘Artificially Irradiated’. These types of particulars are displayed prominently on the grading report below ‘origin’ in the ‘color’ portion of the report.

Pros and disadvantages

The HPHT remedy of diamonds is a controversial situation due to the fact it has both strengths and disadvantages. These are additional mentioned as beneath.

Positive aspects

  • The remedy is long term and diamonds are steady in the typical situations of wear and treatment.
  • It can significantly change the shade of brownish diamonds to make it much more captivating. Mild brown color diamonds can be rendered nearly colorless using this procedure.


  • The approach brings about surface area graphitization and the diamond wants to be polished to eliminate it.
  • It is hard to differentiate in between standard pure diamonds and HPHT dealt with diamonds.
  • It can bring about marginal fat decline in a diamond.
  • It can reduce the clarity of the stone.


As HPHT has turn into additional commercially offered, right now there are different methods accessible to detect if your stone has been HPHT processed or not. At the fundamental stage diamonds above .5 carat can only be HPHT dealt with. A skilled gemologist may possibly use products like the SSEF spotter and crossed polarization filter to detect the same. DiamondSure is also used to individual cape diamonds from the rest. At the upcoming stage FTIR and UVVIS spectroscopes are employed and synthetic and PT taken care of diamonds can very easily be recognized ere. In addition to this, renowned laboratories have lots of other proprietary processes that they use to determine these types of diamonds.

With all innovative equipment it carries on to be complicated to detect HPHT processed diamonds at quite a few cases. It is as a result critical that you buy diamonds from a trusted vendor on-line or offline. Diamonds accompanied with a certification from a reputed laboratory like GIA also ensure that diamonds are absolutely natural. You could also choose signature or best of the line branded diamonds to safeguard yourself. Eventually, if you can not afford GIA stones, make certain to opt for a diamond that is accompanied by a certificate from a renowned laboratory.

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