crazy Q...does each diamond have its own dominant color sparkles?

[Dancing Fire]

some diamonds show more green sparkles ? some show more blue sparkles? some show more red sparkles?

 

[strmrdr]

depends on the lighting more than the diamond.
Diamonds with great optical symmetry might produce more pure tones in some cases.

 

[LGK]

Well, each fire flash is actually the full spectrum- redorangeyellowgreenbluepurple. You might see one color first depending on the angle you''re observing from, but if you verrrry slowly tip the stone, you can watch the individual flash of fire change to the next color in the spectrum. Like, you might see a green flash- if you hold the stone still, so you''re still seeing it, then slowly tip it, it''ll change to blue (or yellow) then purple (or orange). Did I explain that well? It''s late, probably not!

So I guess no, to answer your question more directly.

 

[strmrdr]

Date: 2/13/2009 3:35:10 AM
Author: LittleGreyKitten
Well, each fire flash is actually the full spectrum- redorangeyellowgreenbluepurple. You might see one color first depending on the angle you''re observing from, but if you verrrry slowly tip the stone, you can watch the individual flash of fire change to the next color in the spectrum. Like, you might see a green flash- if you hold the stone still, so you''re still seeing it, then slowly tip it, it''ll change to blue (or yellow) then purple (or orange). Did I explain that well? It''s late, probably not!


So I guess no, to answer your question more directly.

not exactly true.

 

[LGK]

Huh, that''s what I see when I look at the sparkles of my ring... What would you say otherwise, I''m curious?

(And I really should go to bed now!)

Date: 2/13/2009 3:41:30 AM
Author: strmrdr

Date: 2/13/2009 3:35:10 AM
Author: LittleGreyKitten
Well, each fire flash is actually the full spectrum- redorangeyellowgreenbluepurple. You might see one color first depending on the angle you''re observing from, but if you verrrry slowly tip the stone, you can watch the individual flash of fire change to the next color in the spectrum. Like, you might see a green flash- if you hold the stone still, so you''re still seeing it, then slowly tip it, it''ll change to blue (or yellow) then purple (or orange). Did I explain that well? It''s late, probably not!


So I guess no, to answer your question more directly.

not exactly true.

 

[strmrdr]

Date: 2/13/2009 3:51:42 AM
Author: LittleGreyKitten
Huh, that''s what I see when I look at the sparkles of my ring... What would you say otherwise, I''m curious?

(And I really should go to bed now!)

Date: 2/13/2009 3:41:30 AM

Author: strmrdr

Date: 2/13/2009 3:35:10 AM

Author: LittleGreyKitten

Well, each fire flash is actually the full spectrum- redorangeyellowgreenbluepurple. You might see one color first depending on the angle you''re observing from, but if you verrrry slowly tip the stone, you can watch the individual flash of fire change to the next color in the spectrum. Like, you might see a green flash- if you hold the stone still, so you''re still seeing it, then slowly tip it, it''ll change to blue (or yellow) then purple (or orange). Did I explain that well? It''s late, probably not!



So I guess no, to answer your question more directly.

not exactly true.

You will rarely get full apparent separation at normal distances due to the size of the virtual facets vs distance.
The largest virtual facets may display it but all wont. (asschers and emeralds are more apt to do so more often because of the large virtual facets)
In other words you get mixing.
Add in 2 eyed view and it is even less common, it is more visible in videos.
Some colors are rarely seen at all due to the RI and the angles typically involved.
This video clearly shows how the larger virtual facets do so the smaller ones don''t.
http://www.vimeo.com/3177742

 

[John P]

Date: 2/13/2009 4:04:48 AM
Author: strmrdr

You will rarely get full apparent separation at normal distances due to the size of the virtual facets vs distance.
The largest virtual facets may display it but all wont. (asschers and emeralds are more apt to do so more often because of the large virtual facets)
In other words you get mixing.
Add in 2 eyed view and it is even less common, it is more visible in videos.
Some colors are rarely seen at all due to the RI and the angles typically involved.
This video clearly shows how the larger virtual facets do so the smaller ones don''t.
http://www.vimeo.com/3177742

In addition to the virtual facet equation there is also lighting and human physiology involved. It''s very cool and interesting.

Did you ever wonder why you see so many crazy colorful sparkles in bright direct lighting? Much of it has to do with pupil dilation.

1. In soft light, if your pupils are wide open, the dispersed light has a better chance of recombining by the time it hits the retina, and when we see all the colors of the spectrum we perceive it as white light (modified NYSOA graphic).

2. In bright light your pupils are not so dilated and there is a better chance the dispersion will get "clipped" before it hits the retina, so you will perceive color. While this illustration is not technically accurate it serves the purpose (modified NYSOA graphic).

If you have ever looked at a well-cut diamond in bright sunlight you know that the inside of the diamond will appear dark but you''ll see crazy colorful sparkle from it. This is because your pupils close to protect your eyes from the bright sunlight, but in doing so they are very effectively clipping dispersion, so you see color in abundance.

(originally posted in this thread - along with a groovy Pink Floyd album cover graphic)

 

[strmrdr]

Thanks Sir John for posting the rest of the story.

 

[John P]

Date: 2/13/2009 2:35:11 PM
Author: strmrdr
Thanks Sir John for posting the rest of the story.

Quite welcome. The properties of virtual facets, coupled with different illumination scenarios and human physiology, are explaining a lot of the whys and wherefores of classic configurations, and are exciting when exploring new ones.

 

[strmrdr]

Date: 2/13/2009 2:40:57 PM
Author: John Pollard

Date: 2/13/2009 2:35:11 PM

Author: strmrdr

Thanks Sir John for posting the rest of the story.

Quite welcome. The properties of virtual facets, coupled with different illumination scenarios and human physiology, are explaining a lot of the whys and wherefores of classic configurations, and are exciting when exploring new ones.

very true :}
VF''s are my favorite topic and I love an opportunity to discuss them.
They are the key to diamond design.

 

[Garry H (Cut Nut)]

Date: 2/13/2009 3:51:42 AM
Author: LittleGreyKitten
Huh, that''s what I see when I look at the sparkles of my ring... What would you say otherwise, I''m curious?

(And I really should go to bed now!)

Date: 2/13/2009 3:41:30 AM
Author: strmrdr

Date: 2/13/2009 3:35:10 AM
Author: LittleGreyKitten
Well, each fire flash is actually the full spectrum- redorangeyellowgreenbluepurple. You might see one color first depending on the angle you''re observing from, but if you verrrry slowly tip the stone, you can watch the individual flash of fire change to the next color in the spectrum. Like, you might see a green flash- if you hold the stone still, so you''re still seeing it, then slowly tip it, it''ll change to blue (or yellow) then purple (or orange). Did I explain that well? It''s late, probably not!


So I guess no, to answer your question more directly.

not exactly true.

Green (and yellow) are not seen very often because of the effect that John is describing.
http://journal.pricescope.com/Articles/50/5/Letter-to-the-Editor-of-the-Australian-Gemmologist.aspx
this is part of an explanation of a mathematical error Sergey picked up in GIA''s research that the GIA Facetware cut grade system was based on.
There is a relevant explanation on this page

 

[coatimundi_org]

With my old cuts, I see far more fire color in low (pupil dilated) light than in sunlight--even under a tree. Is that generally, because of the larger facets?

 

[strmrdr]

Date: 2/13/2009 3:02:48 PM
Author: coatimundi
With my old cuts, I see far more fire color in low (pupil dilated) light than in sunlight--even under a tree. Is that generally, because of the larger facets?

technically because of the dilated pupils but at the diamond level it is the larger VF''s.

 

[coatimundi_org]

Date: 2/13/2009 3:06:56 PM
Author: strmrdr

Date: 2/13/2009 3:02:48 PM

Author: coatimundi

With my old cuts, I see far more fire color in low (pupil dilated) light than in sunlight--even under a tree. Is that generally, because of the larger facets?

technically because of the dilated pupils but at the diamond level it is the larger VF's.

ah--thanks Storm! And thanks for the cool tutorial John P.!

eta: my rb shows more spectral colors under a tree--sunny day. Makes sense.

 

[Dancing Fire]

seem like i see more green sparkles than any other color on my wife''s ring.

 

[strmrdr]

Date: 2/13/2009 7:16:12 PM
Author: Dancing Fire
seem like i see more green sparkles than any other color on my wife''s ring.

Green and blue will be the most common fire colors in pretty much any cut.

 

[strmrdr]

Here is the reason....
You mix blue with green and you get bluish green or greenish blue.
They strengthen each other.