can all diamonds be Irradiated any color?

[lasugar]

Hi there,

with HPHT, I was reading that 98% of diamonds can take the basic HPHT colors, but only 2% can take pink colors, or light colors.


With Irraditation, can all diamonds be colored in any color, like so far I haven''t read anything about type 1 and type 2 diamonds for this treatment.

thanks

 

[Tom Gelb]

Date: 3/7/2010 10:57:04 AM
Author:lasugar
Hi there,

with HPHT, I was reading that 98% of diamonds can take the basic HPHT colors, but only 2% can take pink colors, or light colors.


With Irraditation, can all diamonds be colored in any color, like so far I haven''t read anything about type 1 and type 2 diamonds for this treatment.

thanks

Hello Lasugar,

In response to your first paragraph I fear there is a great deal of oversimplification, and it may be beneficial for a brief explanation of how these treatments work, so here it goes. HPHT treatment is a very powerful method of treating a diamond which can cause the atoms within a diamond''s lattice to aggregate differently, thus causing a change of color. Type 1 diamonds contain a good deal of nitrogen within the lattice and the aggregation of nitrogen is usually what gives rise to color in a diamond. In the much more rare type 2 diamonds there is none or very little detectable nitrogen and the treatment can cause a realingment of the carbon atoms such that the brown color of these diamonds disappears and the underlying pink or blue (if indeed they are there) become visible. If there is not color underlying the brown type 2 diamond then the resulting diamond can be colorless. Thus type 2 diamonds treated by HPHT can be pink, blue or colorless. Type 1 HPHT diamonds can be greenish yellow or orange (again this is due to the newly aggregated nitrogen in the diamond lattice). There also can be failures of this type of treatment, where no change of color occurs or the color of the diamond before treatment is so strong that the change is immaterial.

Irradiation treatment does a different type of damage to the crystal lattice by knocking the nitrogen or carbon out of their places in the crystal lattice and creating vacancies where they used to be. These vacancies cause a diamond to look green. If these diamonds are subsequently annealed (heat treated) then the resulting color can be yellow, greenish yellow, brownish orange, or in very rare cases deep pink or red (this is again to the nitrogen in the diamond, in this case the nitrogens are not attached to each other, but by themselves. These diamonds are called type 1b and they represent less that 1% of yellow diamonds). As with HPHT diamonds the resulting color has a great deal to do with the starting material, thus a dark brown type 1 diamond will likely be dark brown after irradiation because it is just too dark for any other colors to be visible.

I am unsure if this answers all of your questions, but I think it is a start.

Good luck.

 

[WinkHPD]

Date: 3/7/2010 12:00:21 PM
Author: Tom Gelb

Date: 3/7/2010 10:57:04 AM
Author:lasugar
Hi there,

with HPHT, I was reading that 98% of diamonds can take the basic HPHT colors, but only 2% can take pink colors, or light colors.


With Irraditation, can all diamonds be colored in any color, like so far I haven''t read anything about type 1 and type 2 diamonds for this treatment.

thanks

Hello Lasugar,

In response to your first paragraph I fear there is a great deal of oversimplification, and it may be beneficial for a brief explanation of how these treatments work, so here it goes. HPHT treatment is a very powerful method of treating a diamond which can cause the atoms within a diamond''s lattice to aggregate differently, thus causing a change of color. Type 1 diamonds contain a good deal of nitrogen within the lattice and the aggregation of nitrogen is usually what gives rise to color in a diamond. In the much more rare type 2 diamonds there is none or very little detectable nitrogen and the treatment can cause a realingment of the carbon atoms such that the brown color of these diamonds disappears and the underlying pink or blue (if indeed they are there) become visible. If there is not color underlying the brown type 2 diamond then the resulting diamond can be colorless. Thus type 2 diamonds treated by HPHT can be pink, blue or colorless. Type 1 HPHT diamonds can be greenish yellow or orange (again this is due to the newly aggregated nitrogen in the diamond lattice). There also can be failures of this type of treatment, where no change of color occurs or the color of the diamond before treatment is so strong that the change is immaterial.

Irradiation treatment does a different type of damage to the crystal lattice by knocking the nitrogen or carbon out of their places in the crystal lattice and creating vacancies where they used to be. These vacancies cause a diamond to look green. If these diamonds are subsequently annealed (heat treated) then the resulting color can be yellow, greenish yellow, brownish orange, or in very rare cases deep pink or red (this is again to the nitrogen in the diamond, in this case the nitrogens are not attached to each other, but by themselves. These diamonds are called type 1b and they represent less that 1% of yellow diamonds). As with HPHT diamonds the resulting color has a great deal to do with the starting material, thus a dark brown type 1 diamond will likely be dark brown after irradiation because it is just too dark for any other colors to be visible.

I am unsure if this answers all of your questions, but I think it is a start.

Good luck.

(First off, welcome both of you to Pricescope, I see you are both at the time I write this only one post apart and that you both joined today.)

Wow, luckily I read your post before responding. What a wonderfully complete answer to a "simple" question. I hope you are to become a regular here, you obviously payed attention during class!

Wink

 

[lasugar]

oh wow, thats a big and good answer!
Thanks Tom.

well, we''ll just see what irradiated colors I end up with.
I want a nice light pink, what would u suggest if it''s irradiated (my manu. dosen''t do HPHT)

 

[Tom Gelb]

Wink,

Thank you for the complement, I appreciate it. In fact I used to teach the class!

Lasugar,

A light pink is a tall order for an irradiated diamond, not sure if it can be done on purpose, and when to do turn pink it is a deeper pink. HPHT can produce a light pink, but that is even harder to find the right starting material, and even then there is no guarantee. The only way you can get a light pink through treatment is through coating, which is not stable at all.

Sorry.

Good luck.

 

[Richard Sherwood]

Very succinct, accurate and understandable post, Tom.

Nice to have you aboard.