Rainbow colors in some lighting environments

[prettycat]

I saw there were some diamonds having rainbow colors and fire in some lighting environments, but I have never seen that in my stone. It''s a Whiteflash ACA (0.8 ct, F,VS2), and it does only have WHITE flash and fire.

I went to a local Kay two weeks ago, comparing my stone with a Leon H SI2 just to see the size difference between 0.8 and 1 ct. When they were on my finger side by side, I could see the Leon stone had rainbow colors and mine was only pure white.

I am very curious what caused the difference. I don''t mind the lack of rainbow colors though.

 

[Moh 10]

How can this be?

If they were both on your finger then they got the same light.
How can an ACA not return lots of colors?
The ACA is a superbly-cut diamond and should give off an explosion of colored fire when under a bright light source of a small angle.

I'm mystified.

Perhaps your ACA is not clean.
How do you clean your diamond?
How often?
Do you use hand lotion? - Even if you remove your ring before applying it hand lotion can work its way onto your ring and will dull any diamond.

Any residue on the diamond's surface not only blocks light but it changes the refractive index at the diamond to air surface.
This changes the angle that the light bends when passing through the surface.
Distorting the angle of light from what was intended is not good.
Those angles are precision calculated and polished into the facets of your ACA.

 

[strmrdr]

The leo diamond has extra facets on the pavilion with smaller virtual facets and you were in lighting specifically tuned for it.

 

[Lorelei]

Date: 5/16/2009 1:52:48 PM
Author: strmrdr
The leo diamond has extra facets on the pavilion with smaller virtual facets and you were in lighting specifically tuned for it.

Yep.

 

[prettycat]

Is a super-ieal cut stone supposed to have colorful fire? My ACA is sparkly and briiliant, but I have never seen the strong colorful fire in it.
I am fine with it.

 

[strmrdr]

Date: 5/16/2009 2:49:31 PM
Author: prettycat
Is a super-ieal cut stone supposed to have colorful fire? My ACA is sparkly and briiliant, but I have never seen the strong colorful fire in it.

I am fine with it.

In the right lighting it will have it.

 

[Lorelei]

Date: 5/16/2009 2:51:08 PM
Author: strmrdr

Date: 5/16/2009 2:49:31 PM
Author: prettycat
Is a super-ieal cut stone supposed to have colorful fire? My ACA is sparkly and briiliant, but I have never seen the strong colorful fire in it.

I am fine with it.

In the right lighting it will have it.

Ditto again.

 

[amyjokerette]

Date: 5/16/2009 1:17:53 PM
Author:prettycat
I saw there were some diamonds having rainbow colors and fire in some lighting environments, but I have never seen that in my stone. It''s a Whiteflash ACA (0.8 ct, F,VS2), and it does only have WHITE flash and fire.

I went to a local Kay two weeks ago, comparing my stone with a Leon H SI2 just to see the size difference between 0.8 and 1 ct. When they were on my finger side by side, I could see the Leon stone had rainbow colors and mine was only pure white.


I am very curious what caused the difference. I don''t mind the lack of rainbow colors though.

This is not an answer to your question... but rather a side note. When comparing the size difference between your 1 ct diamond and a .80ct Leo diamond it may not give you a real life comparison. Leo''s tend to be cut deep, and therefore they will faceup smaller. You might get a more accurate comparison of size by trying on a diamond with more "ideal" proportions... or proportions similar to your current diamond.

 

[Garry H (Cut Nut)]

Light return can be the enemy of fire - if there is a lot of light return then the fire can be washed out

 

[Diamond Explorer]

Date: 5/16/2009 11:07:28 PM
Author: Garry H (Cut Nut)
Light return can be the enemy of fire - if there is a lot of light return then the fire can be washed out

I think that is why the brightest diamond may not be the most beautiful diamond to all eyes.

 

[Sharon101]

Date: 5/16/2009 11:07:28 PM
Author: Garry H (Cut Nut)
Light return can be the enemy of fire - if there is a lot of light return then the fire can be washed out

That`s interesting.

 

[Garry H (Cut Nut)]

Date: 5/16/2009 11:29:05 PM
Author: Diamond Explorer

Date: 5/16/2009 11:07:28 PM
Author: Garry H (Cut Nut)
Light return can be the enemy of fire - if there is a lot of light return then the fire can be washed out

I think that is why the brightest diamond may not be the most beautiful diamond to all eyes.

Drop the 1 million jewelry store lighting back to habitable levels Jonathon, and do the same test. see which diamond wins out then.

 

[Diamond Explorer]

Date: 5/17/2009 12:29:34 AM
Author: Garry H (Cut Nut)

Date: 5/16/2009 11:29:05 PM

Author: Diamond Explorer

Date: 5/16/2009 11:07:28 PM

Author: Garry H (Cut Nut)

Light return can be the enemy of fire - if there is a lot of light return then the fire can be washed out

I think that is why the brightest diamond may not be the most beautiful diamond to all eyes.

Drop the 1 million jewelry store lighting back to habitable levels Jonathon, and do the same test. see which diamond wins out then.

Ofcourse Garry, I was not really commenting on this particular case but speaking more generally.

 

[WinkHPD]

Date: 5/16/2009 11:07:28 PM
Author: Garry H (Cut Nut)
Light return can be the enemy of fire - if there is a lot of light return then the fire can be washed out

If you said "is the enemy of fire" rather than "can" I would have to vociferously dissagree with you Garry. I can not catagorically state that it is incorrect, just that it is not correct all the time. I deal with diamonds that are cut to the highest standards and have AGS 0 light return and wonderful amounts of fire, so I know that it is not always correct.

I think it may be one of the myths of our business, because I hear so many people say it, yet most of the AGS 0 cut diamonds and AGS 1 cut diamonds that have the AGS 0 light return, at least the ones that I have seen, also exhibit great fire.

Wink

 

[strmrdr]

Personally my opinion is that...
White Light return can be the enemy of fire for a given light condition.
Also
Fire can be the enemy of white Light return for a given lighting condition.

It is all in where the designer and or cutter places the balance points.

A well cut diamond to me is bright and fiery in the right light conditions for each.
In some lighting you will get a mix but less often than you would think.
I don''t consider a diamond that is showing brightness and you tilt it 20 degrees and it gives one flash of fire to be a mix.

 

[Stephan]

My personal experience with rounds is that shallower combos often have more fire under spot lighting. I also prefer longer lower girdles: when the lower girdle angle is close to the pavilion main angle, things seems to move faster. In such shallow combos, I also prefer long star facets, I think it brings a nice contrast when the upper girdle has a higher angle than the lower girdle, while the crown has a smaller angle than the pavilion main angle. But that''s just my little experience, my personal preference in matter of RB.

 

[Demon]

Something weird I've noticed (kind of on topic?) is that even though my eyes don't always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones 'naked' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

 

[Lula]

I''ve noticed that, too, Demon, especially with mirrors. Can someone more knowledgeable about physics and light return comment? Thanks.

 

[Daisi2112]

Date: 5/17/2009 1:28:23 PM
Author: Demon
Something weird I''ve noticed (kind of on topic?) is that even though my eyes don''t always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones ''naked'' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

Me too, I notice the same thing.

 

[Garry H (Cut Nut)]

Date: 5/17/2009 3:07:26 PM
Author: Daisi2112

Date: 5/17/2009 1:28:23 PM
Author: Demon
Something weird I''ve noticed (kind of on topic?) is that even though my eyes don''t always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones ''naked'' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

Me too, I notice the same thing.

it is exactly what i was talking about - the light is so bright - but further away you see the colors - there is something on Octonus.com to describe it - but have to go now

 

[Serg]

Date: 5/17/2009 12:38:15 AM
Author: Wink

Date: 5/16/2009 11:07:28 PM

Author: Garry H (Cut Nut)

Light return can be the enemy of fire - if there is a lot of light return then the fire can be washed out

If you said ''is the enemy of fire'' rather than ''can'' I would have to vociferously dissagree with you Garry. I can not catagorically state that it is incorrect, just that it is not correct all the time. I deal with diamonds that are cut to the highest standards and have AGS 0 light return and wonderful amounts of fire, so I know that it is not always correct.


I think it may be one of the myths of our business, because I hear so many people say it, yet most of the AGS 0 cut diamonds and AGS 1 cut diamonds that have the AGS 0 light return, at least the ones that I have seen, also exhibit great fire.


Wink

Wink, what definition of Light return do you use?
could you publish explanation what LR is and how we can calculate it?

 

[Serg]

Date: 5/17/2009 3:45:42 PM
Author: Garry H (Cut Nut)

Date: 5/17/2009 3:07:26 PM

Author: Daisi2112

Date: 5/17/2009 1:28:23 PM

Author: Demon

Something weird I''ve noticed (kind of on topic?) is that even though my eyes don''t always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones ''naked'' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

Recently one my partner sent me files 2 princes which is more bright than RBC.
I checked these 3D files in DC. DC LR was low. But because my partner was sure these princes are better than round (and send me several photos what confirm it), I come to check it.

We started from standard gemological light. Princess were definitely better.

I found 2 reasons :
1)Princess have big Pavilion leakage ,( it improve cut significantly in gemological light ). It is well know
2) Second reason is more interesting . when we switch off gemological light , princess become a little bit less bright , but RBC become much more bright

In gemological RBC has several big bright facets , other parts was too dark. Princess has not any big bright flashes
Without gemological light princess lost light what it received through Pavilion Leakage ( 10-15%)
RBC lost ALL big bright facets and become brighter , without any dark zones. ( of course RBC reflected less light, but subjectively it become more bright )



Me too, I notice the same thing.

it is exactly what i was talking about - the light is so bright - but further away you see the colors - there is something on Octonus.com to describe it - but have to go now

 

[strmrdr]

Date: 5/17/2009 1:28:23 PM
Author: Demon
Something weird I''ve noticed (kind of on topic?) is that even though my eyes don''t always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones ''naked'' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

1: you only see those flashes that reach the eye directly.
2: at close range the flashes mix to white, the entire spectrum does not have to be present for it to look white with bright light sources.
3: the light beams separate with distance and spread apart from each other as they are at slightly different angles.

For example here might be the flashes coming off a diamond and you only see a small portion of them directly for example only those circled in red may hit the eye.
But you would see far more reflected off a large object.

 

[diagem]

Date: 5/17/2009 4:24:06 PM
Author: Serg

Date: 5/17/2009 12:38:15 AM
Author: Wink

Date: 5/16/2009 11:07:28 PM

Author: Garry H (Cut Nut)

Light return can be the enemy of fire - if there is a lot of light return then the fire can be washed out

If you said ''is the enemy of fire'' rather than ''can'' I would have to vociferously dissagree with you Garry. I can not catagorically state that it is incorrect, just that it is not correct all the time. I deal with diamonds that are cut to the highest standards and have AGS 0 light return and wonderful amounts of fire, so I know that it is not always correct.


I think it may be one of the myths of our business, because I hear so many people say it, yet most of the AGS 0 cut diamonds and AGS 1 cut diamonds that have the AGS 0 light return, at least the ones that I have seen, also exhibit great fire.


Wink

Wink, what definition of Light return do you use?
could you publish explanation what LR is and how we can calculate it?

Great questions Serg..., I am interesting on reading some of the definitions...
I suppose everyone translates ''light return'' a bit differently...

 

[Lynn B]

PrettyCat, try this (totally LOW TECH

) experiment:

Clean your ring very well.
Stand in a room with one window, with your back to the window, holding your ring straight out in front of you.
You should see the rainbow colors you are looking for.

 

[Demon]

Date: 5/17/2009 3:45:42 PM
Author: Garry H (Cut Nut)

Date: 5/17/2009 3:07:26 PM
Author: Daisi2112

Date: 5/17/2009 1:28:23 PM
Author: Demon
Something weird I''ve noticed (kind of on topic?) is that even though my eyes don''t always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones ''naked'' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

Me too, I notice the same thing.

it is exactly what i was talking about - the light is so bright - but further away you see the colors - there is something on Octonus.com to describe it - but have to go now

Thanks - it''d be great if you could point me to it when you get a chance (there''s quite a bit on there!)

 

[Demon]

Date: 5/17/2009 4:43:18 PM
Author: Serg

Date: 5/17/2009 3:45:42 PM
Author: Garry H (Cut Nut)

Date: 5/17/2009 3:07:26 PM

Author: Daisi2112

Date: 5/17/2009 1:28:23 PM

Author: Demon

Something weird I''ve noticed (kind of on topic?) is that even though my eyes don''t always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones ''naked'' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

Recently one my partner sent me files 2 princes which is more bright than RBC.
I checked these 3D files in DC. DC LR was low. But because my partner was sure these princes are better than round (and send me several photos what confirm it), I come to check it.

We started from standard gemological light. Princess were definitely better.

I found 2 reasons :
1)Princess have big Pavilion leakage ,( it improve cut significantly in gemological light ). It is well know
2) Second reason is more interesting . when we switch off gemological light , princess become a little bit less bright , but RBC become much more bright

In gemological RBC has several big bright facets , other parts was too dark. Princess has not any big bright flashes
Without gemological light princess lost light what it received through Pavilion Leakage ( 10-15%)
RBC lost ALL big bright facets and become brighter , without any dark zones. ( of course RBC reflected less light, but subjectively it become more bright )



Me too, I notice the same thing.

it is exactly what i was talking about - the light is so bright - but further away you see the colors - there is something on Octonus.com to describe it - but have to go now

Ok, I kind of get what you''re saying about leakage and different lighting, but what is standard gemological lighting, exactly?

 

[Demon]

Date: 5/17/2009 4:45:11 PM
Author: strmrdr

Date: 5/17/2009 1:28:23 PM
Author: Demon
Something weird I've noticed (kind of on topic?) is that even though my eyes don't always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones 'naked' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

1: you only see those flashes that reach the eye directly.
2: at close range the flashes mix to white, the entire spectrum does not have to be present for it to look white with bright light sources.
3: the light beams separate with distance and spread apart from each other as they are at slightly different angles.

For example here might be the flashes coming off a diamond and you only see a small portion of them directly for example only those circled in red may hit the eye.
But you would see far more reflected off a large object.

Thank you. You are so helpful in breaking this stuff down into a diamonds-for-dummies format.

(and I mean that in a most positive way!)

 

[strmrdr]

Date: 5/17/2009 7:24:52 PM
Author: Demon
Ok, I kind of get what you're saying about leakage and different lighting, but what is standard gemological lighting, exactly?

broad spectrum fluorescent tubes over the side of the diamond at close range.
Here is why it is deceptive...
Top image is simulated gemological lighting second is simulated real world over a dark background.
light on it looks bright, light off it looks ugly which it is.

 

[Garry H (Cut Nut)]

Date: 5/17/2009 7:22:41 PM
Author: Demon

Date: 5/17/2009 3:45:42 PM
Author: Garry H (Cut Nut)

Date: 5/17/2009 3:07:26 PM
Author: Daisi2112

Date: 5/17/2009 1:28:23 PM
Author: Demon
Something weird I''ve noticed (kind of on topic?) is that even though my eyes don''t always pick up on individual flashes of fire, when I see the diamond reflected in a window or a mirror (same lighting) there seems to be tons of flashes. Is this something about the properties of glass, or can the eyes not keep up with the stones ''naked'' flashes as well, somehow? Some magnification or something? (I even see more flases reflected in the tile of the shower than looking at the diamond directly??)

Me too, I notice the same thing.

it is exactly what i was talking about - the light is so bright - but further away you see the colors - there is something on Octonus.com to describe it - but have to go now

Thanks - it''d be great if you could point me to it when you get a chance (there''s quite a bit on there!)

Here you are demon
http://www.cutstudy.com/cut/english/grading1/