Type IA and HPHT?

[DevilsAdvocate]

Slipped to bottom of page three without a reply! Guess that is not good news!

I sure could use some of your thoughts on this!

It appears increased numbers of Type IA diamonds are given HPHT treatment.

Do we have to suspect all IAs now, as well as Type IIA?

Which IA diamonds should be lab tested for HPHT?

Any ideas as to the numbers of these being done?

Thank you for any insights. I will try getting in touch with some folks that do the treatment after the weekend.

 

[oldminer]

I have asked an authority on this subject to answer or to tell me so that I may reply to you. Hope he knows.

 

[oldminer]

Here is a reply:

Dave Atlas wrote:
It appears increased numbers of Type IA diamonds are given HPHT treatment.

Yup

Do we have to suspect all IAs now, as well as Type IIA?

Fancy colors, definitely yes.
I've been told that they have been able to eliminate the strong yellow green fluorescence, and are producing good yellows.
I'll be getting a chance to see some pre and post processed stone in the next few months..
Stuff is being done in Germany, and probably in the far east also

Which IA diamonds should be lab tested for HPHT?

Fancy colors

Any ideas as to the numbers of these being done?

Small amounts, from what I've heard. I've heard of some olive greens and yellows getting by the big boys as natural

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[DevilsAdvocate]

David,

Appreciate the information. No doubt this will be affecting the trade more as time goes on.

Your information source mentioned a couple of these slipped by some experts undetected. Do the major labs check every diamond for treatments, or just certain ones?

The following colors, as far as I could find out so far, have been recorded as the results of IAs given HPHT.Most are fancy colors, some pale, some intense: yellow, orange, green, yellow green, green yellow,pink, and purple pink. Most are converted from yellows and browns.I read that if the Type is Ia/b it could result in colorless.

It looks like more will be happening with this. I will pass on any relevant information I get, and will much appreciate anyone else doing the same!

Thanks again.

 

[solange]

What are you referring to as a 1A diamond? My stone is listed as 1A American cut. Does this information apply to white stones as well?

 

[oldminer]

1A cut is NOTHING to do with 1A type//// 1A type is a different issue having mostly to do with nitrogen in the diamond crystal.

The stones "getting by" means that major (and minor) labs are missing the detection of some HTHP diamonds even though the big labs are testing every diamond.

 

[elmo]

This article by James Shigley is a good intro to the topic: Diamond Types I/II ab.