Question on seeing "fire" instead of white light

[Kim N]

Is it always true that steeper crown angles and smaller tables contribute to more fire? What if I''m comparing two stones, and one has a shallower crown angle but still a smaller table? How would I be able to tell, without seeing it (online purchase), which is more "firey"?

These are the two I''m considering:

Round diamond #1:
Depth: 60.5
Table: 56
Crown Angle: 34.1
Crown %: 14.9
Pavilion Angle: 40.8
Pavilion %: 43
Girdle: Thin to Slightly Partly Polished

Round diamond #2:
Depth: 61.2
Table: 57
Crown Angle: 35
Crown %: 15.1
Pavilion Angle: 40.9
Pavilion %: 43.1
Girdle: Medium to Slightly thick Faceted

I would like to buy the one that''s more firey but I don''t know which one it would be without looking at it.

Also, what''s the difference between a "super-ideal" (e.g. ACA, SuperbCert) and a regular ideal stone if both of them are AGS000? Is there any advantage to buying a super-ideal?

I''d appreciate any help or advice. Thanks in advance!

 

[strmrdr]

with those combos it comes down to lgf% as too how fiery they are.

That said 35/40.9 is not a combo I like much.

34.1/40.8 can be plenty fiery with the right lgf%
but the combo is more geared towards light return.

56% and 57% neither is a small table.
60% is large and 54% is small.

Between those 2 id take the first depending on the minor facets.

A diamond doesnt have to be branded to be super-ideal, GOG has a bunch of unbranded super-ideal diamonds.
Just because a diamond is branded doesnt make it a great diamond.

The difference between a super-ideal and ideal in good light conditions isnt going to be much but in extreme light conditions there may be a difference.

 

[strmrdr]

For fire over white light return look for one of 2 things but not in the same diamond:
fic on the hca or a LGF% in the 75%-76% range in a tic on the hca.

 

[Mara]

I agree I like the first one better between the two...but the second would be beautiful most likely as well. Both seem like they''d be well-cut just from the numbers. I can''t say which one would be more fiery, but I would venture to estimate that the first one would be more brilliant possibly? With the lower depth and the shallower crown angle than the second stone?

Maybe an expert can chime in?? Can you ask the vendors what they think about the fire vs brilliance of each stone?

 

[oldminer]

Count on apparent fire in a diamond to be far more affected by the lighting conditions than by how it is cut. I don''t think anyone is cutting ideal rounds to maximize "fire" in regualr lighting conditions. There is nothing wrong about a beautiful spectal display when it occurs, but it occurs in all well cut diamonds. I have never met anyone who had a diamond they bought for high fire at the loss of white light returnm, scintillation or contrast..... I beleive these three most important aspects outweigh fire, but anyone is entitled to create their own special requirements..

 

[glitterata]

This may be taking the thread off track--I apologize if so--but what''s the difference between scintillation and contrast?

 

[strmrdr]

scintillation == dynamic fire combined with dynamic contrast == one/off flashes of light as the diamond is moved.

contrast == difference between the bright and dark areas of a diamond.

 

[Kim N]

Thank you, everyone, for the replies. I appreciate your help.

Strmrdr, I had some questions:

>> That said 35/40.9 is not a combo I like much.

I was wondering why that combo isn''t one you like as much? Does it diminish brilliance or diminish something else?
>> 34.1/40.8 can be plenty fiery with the right lgf%
but the combo is more geared towards light return.
For fire over white light return look for one of 2 things but not in the same diamond:
fic on the hca or a LGF% in the 75%-76% range in a tic on the hca.

Both diamonds are TIC on the HCA. Diamond #1 was 0.9 on the HCA, and diamond #2 was 1.9. What is an LGF%? Where do I find that on the HCA?
>> A diamond doesnt have to be branded to be super-ideal, GOG has a bunch of unbranded super-ideal diamonds.
Just because a diamond is branded doesnt make it a great diamond.
How can I tell on GOG''s website which ones are unbranded super-ideal vs. unbranded ideal?

Thanks again for everyone''s help.

 

[strmrdr]

Date: 10/9/2005 6:46:11 PM
Author: jellybeans
Thank you, everyone, for the replies. I appreciate your help.

Strmrdr, I had some questions:

my answers in bold, some of it is over simplified but should give the general idea


>> That said 35/40.9 is not a combo I like much.



I was wondering why that combo isn't one you like as much? Does it diminish brilliance or diminish something else?

35 degree crown works better with a shallower pavillian. Its getting into the step deep range where you lose some brighness and some spread.
They can be nice diamonds but not top end in my opinion

>> 34.1/40.8 can be plenty fiery with the right lgf%

but the combo is more geared towards light return.

For fire over white light return look for one of 2 things but not in the same diamond:

fic on the hca or a LGF% in the 75%-76% range in a tic on the hca.



Both diamonds are TIC on the HCA. Diamond #1 was 0.9 on the HCA, and diamond #2 was 1.9. What is an LGF%? Where do I find that on the HCA?

hca doesnt rate the lgf% or other minor facets the hca is a tool to tell if the c/p angle combo works. minor facet info is here: http://www.goodoldgold.com/minor_facets.htm

>> A diamond doesnt have to be branded to be super-ideal, GOG has a bunch of unbranded super-ideal diamonds.

Just because a diamond is branded doesnt make it a great diamond.

How can I tell on GOG's website which ones are unbranded super-ideal vs. unbranded ideal?

the ones marked h&a are in most cases super-ideals or they perform like super-ideals on the direct performance testing. the ideals are marked ideal or near h&a. whiteflash.com has a simular split the super-ideals will be marked ACA and the ideals/near h&a as Expert Selection. The ideal/near h&a diamonds and the WF ES diamonds can be exellent values for the money with most of the performance of the super-ideals for less money.

Thanks again for everyone's help.