Diamond synthesis & crystal growth topics, questions

[kcherian]

Two topics/questions to start with:


1. Diamond growth from non-metallic solvent catalysts:

Impurity inclusions in natural diamonds tend to be a variety of minerals whereas in synthetic diamonds they tend to be the metal solvent-catalysts. The impurity inclusions therefore indicate the composition of the environment in which crystal growth took place; natural diamond crystal growth therefore must have taken place in non-metallic solvent catalyst environment.

Would be interested to know if the current HPHT gem diamond crystal growers are looking into the possibility of diamond crystal growth in non-metallic solvent-catalysts? What would be the typical characteristics, including color, of crystals grown in such enviroments? Would they be different from those grown in/from metal solvent-catalysts?


2. Surface microstructures of HPHT man-made gem diamond in comparison with naturals:

The surface microstructures of natural diamonds have been extensively studied and reported (e.g., Microstructures of Diamond Surfaces by Prof. Samuel Tolansky, N.A.G. Press, London). The natural octahedral faces of diamonds generally exhibit features called trigons and cubic faces, quadrons, etc.

What typical surface microstructures would the HPHT as-grown gem diamond octahedral and cubic (and also other less common crystallographic) faces, show? Anything comparable to the natural diamonds, or are the surface microstructures of HPHT man-made gem diamonds totally different?


Karl

 

[Clark McEwen]

Date: 6/28/2008 4:32:48 AM
Author:kcherian
Two topics/questions to start with:




1. Diamond growth from non-metallic solvent catalysts:


Impurity inclusions in natural diamonds tend to be a variety of minerals whereas in synthetic diamonds they tend to be the metal solvent-catalysts. The impurity inclusions therefore indicate the composition of the environment in which crystal growth took place; natural diamond crystal growth therefore must have taken place in non-metallic solvent catalyst environment.


Would be interested to know if the current HPHT gem diamond crystal growers are looking into the possibility of diamond crystal growth in non-metallic solvent-catalysts? What would be the typical characteristics, including color, of crystals grown in such enviroments? Would they be different from those grown in/from metal solvent-catalysts?



2. Surface microstructures of HPHT man-made gem diamond in comparison with naturals:


The surface microstructures of natural diamonds have been extensively studied and reported (e.g., Microstructures of Diamond Surfaces by Prof. Samuel Tolansky, N.A.G. Press, London). The natural octahedral faces of diamonds generally exhibit features called trigons and cubic faces, quadrons, etc.


What typical surface microstructures would the HPHT as-grown gem diamond octahedral and cubic (and also other less common crystallographic) faces, show? Anything comparable to the natural diamonds, or are the surface microstructures of HPHT man-made gem diamonds totally different?



Karl

Hi Karl,

I think that you will find that producers will be reluctant to answer questions that potentially gets into their IP. General discussion are fine but it is difficult to get into any detail and still protect IP so it is easier to simply avoid the questions. I hope that you understand.

Having said that I have observed what appear to be trigon like features on some of our diamonds

Cheers,
Clark

 

[kcherian]

Date: 7/1/2008 4:49:51 AM
Author: Clark McEwen

Date: 6/28/2008 4:32:48 AM
Author:kcherian


Two topics/questions to start with:






1. Diamond growth from non-metallic solvent catalysts:


Impurity inclusions in natural diamonds tend to be a variety of minerals whereas in synthetic diamonds they tend to be the metal solvent-catalysts. The impurity inclusions therefore indicate the composition of the environment in which crystal growth took place; natural diamond crystal growth therefore must have taken place in non-metallic solvent catalyst environment.


Would be interested to know if the current HPHT gem diamond crystal growers are looking into the possibility of diamond crystal growth in non-metallic solvent-catalysts? What would be the typical characteristics, including color, of crystals grown in such enviroments? Would they be different from those grown in/from metal solvent-catalysts?



2. Surface microstructures of HPHT man-made gem diamond in comparison with naturals:


The surface microstructures of natural diamonds have been extensively studied and reported (e.g., Microstructures of Diamond Surfaces by Prof. Samuel Tolansky, N.A.G. Press, London). The natural octahedral faces of diamonds generally exhibit features called trigons and cubic faces, quadrons, etc.


What typical surface microstructures would the HPHT as-grown gem diamond octahedral and cubic (and also other less common crystallographic) faces, show? Anything comparable to the natural diamonds, or are the surface microstructures of HPHT man-made gem diamonds totally different?



Karl

Hi Karl,

I think that you will find that producers will be reluctant to answer questions that potentially gets into their IP. General discussion are fine but it is difficult to get into any detail and still protect IP so it is easier to simply avoid the questions. I hope that you understand.

Having said that I have observed what appear to be trigon like features on some of our diamonds

Cheers,
Clark

Hi Clark,

Thanks for your response.

Regarding non-metallic catalyst-solvents for diamond crystal growth:
Quite a bit is known and has been published in the scientific/technical literature on diamond growth from non-metallic solvent catalysts; my query about its practical implementation in industry was intended to be a very general one and from a scientific viewpoint. It was not intended to probe into anyone’s IP, and am sorry if that was the impression my query gave. I had heard at least one major research group’s views in this regard, that the significance of this diamond crystal growth route has perhaps not been fully appreciated and adopted by the industry...and I thought this might be of interest to discuss on this educative forum…

Regarding the surface microstructures of diamond:
It is very interesting to know trigon-like features have been observed on BARS grown diamonds; were they all of the same size or different sizes and ‘negatively oriented’? Also, were any crystal growth spirals observed on any of the crystallographic faces? (These would be of interest to a diamond crystal growth scientist!)

Regards,
Karl

 

[kcherian]

"Gemesis on Discovery Channel''s Factory Made Show":

http://www.youtube.com/watch?v=3eun2c9dElc&feature=related

Very interesting indeed.

Congratulations, Clark!

KC

 

[Clark McEwen]

Date: 7/9/2008 7:52:26 PM
Author: kcherian


''Gemesis on Discovery Channel''s Factory Made Show'':


http://www.youtube.com/watch?v=3eun2c9dElc&feature=related


Very interesting indeed.


Congratulations, Clark!


KC


Thanks Karl,

This is the 3rd documentary that has been recorded at our facility in the last 2 months....National Geographic is coming down next. There is a lot of interest in the process and we at Gemesis are more than willing to share it with the world. As you know we are transparent and proud of our accomplishments.

Cheers,
Clark

 

[kcherian]

Date: 7/9/2008 10:04:20 PM
Author: Clark McEwen

Date: 7/9/2008 7:52:26 PM
Author: kcherian


''Gemesis on Discovery Channel''s Factory Made Show'':


http://www.youtube.com/watch?v=3eun2c9dElc&feature=related


Very interesting indeed.


Congratulations, Clark!


KC


Thanks Karl,

This is the 3rd documentary that has been recorded at our facility in the last 2 months....National Geographic is coming down next. There is a lot of interest in the process and we at Gemesis are more than willing to share it with the world. As you know we are transparent and proud of our accomplishments.

Cheers,
Clark

Hi, Clark,

Are links available to the other two documentaries? Please post if possible (or email to karlcherian[at]gmail[dot]com). Thanks!
Yes, your accomplishments are transparent and something you can be really proud of!

Does AOTC / D.Nea have similar documentaries?

Karl

 

[Alexei Zarakhani]

Date: 7/15/2008 1:09:41 AM
Author: kcherian


Does AOTC / D.Nea have similar documentaries?

No, we don''t have "similar documentaries". We don''t feel that they are beneficial to us. Instead, we eagerly show our products - fine blue, pink, colorless and yellow diamonds. As for documentary, there is one - a BBC 60-minute film (1999-2000)called "The Diamond Deception" in which Gemesis and our laboratory are featured. Since then both a process and equipment didn''t undergo fundamental changes visible to general public. If you haven''t watched this film before, I suggest you to see it: ''The Diamond Deception''. It has more depth than "how it is made" clips.