Low LGF%? Need advice on this stone

[strmrdr]

Date: 7/18/2007 2:03:33 AM
Author: JohnQuixote

The AGSL metric is more telling in this case because they include light return values at 0 degress and tilted to 4 compass directions. Jim C from the lab has told me that inside robust t/c/p combos the values in cherry lower half % ranges equal out as soon as you move the diamond because the light-dark ratios reverse themselves. He''s also said much of this is beyond our human cognitive ability to perceive (that for Wink, Alj and Belle) but we''re already nano-spec-ing so I thought what the hey.

Thoughts?

also thinking about this another issue with the AGS metric is one directional source of obstruction don''t match the real world.
On the finger there are many sources and direction of obstruction.
A painting on a white wall may be an obstruction in the green zone, someones shirt in the red, the person standing beside them in the green and red zones.

 

[Garry H (Cut Nut)]

Date: 7/18/2007 3:27:48 AM
Author: strmrdr

Date: 7/18/2007 2:03:33 AM
Author: JohnQuixote

The AGSL metric is more telling in this case because they include light return values at 0 degress and tilted to 4 compass directions. Jim C from the lab has told me that inside robust t/c/p combos the values in cherry lower half % ranges equal out as soon as you move the diamond because the light-dark ratios reverse themselves. He''s also said much of this is beyond our human cognitive ability to perceive (that for Wink, Alj and Belle) but we''re already nano-spec-ing so I thought what the hey.

Thoughts?

also thinking about this another issue with the AGS metric is one directional source of obstruction don''t match the real world.
On the finger there are many sources and direction of obstruction.
A painting on a white wall may be an obstruction in the green zone, someones shirt in the red, the person standing beside them in the green and red zones.

Not to mention the actual person looking at the diamond (perhaps the one constant factor?)?

And the orientation of the stone? Should it be tilted to 4 compass directions? (that is two different directions i think John?) And should those directions be at what angles for rounds and what about other shapes?

 

[pyramid]

Wink's point on the previous thread is correct. However some people enjoy dissecting the diamond and finding out about it and consumers here like Ech are probably into some other field like engineering, mathematics etc. and what ever they hash out here with Garry and Storm they will be able to apply that theories to other things, in the same way Garry and Storm may be learning things from their expertise and experience. For instance not consumers but Garry said to Paul that some of his mistakes are what he learns from, here he is getting insight from a Cutter and with Ech he is getting insight from another persons occupation or training. I do think it makes consumer's heads hurt, it did mine but not as much now, I have seemingly through persevering with reading things I couldn't understand and taking some of it in begun to understand more and more of what is being said, I notice a differnce every now and then. I would never as Wink said start to think I know this or that better than those people with engineering or other types of training but I find it interesting. Like some may like gardening some like to read and learn things even if they are not getting a degree in the subject. I think it is discussions like these that keep some people here and buying from the vendors, if some had seen the basic 4 C's we see on other sites, they would not have a reason to stay here and vendors here would be no different from others.

 

[Maisie]

Pyramid I''m not criticising (spelling?) anyone for learning more about diamonds. Its good to learn! I just think that its quite stressful for some people when other peoples perception of what is beautiful and whats not is different. I find that its better for me (and again thats personal to me) to have a look and decide with my eyes instead of my brain.

Mind you that might be an indication that I am just to dim to understand the numbers and what they mean!

 

[echelon6]

Keep in mind I''m all the way in Australia, and theres not a snowball''s chance in hell I''d get to sight the diamonds im considering prior to wiring money. If I''m buying sight unseen, the rock may as well be "numberclean" to me

I do enjoy looking at numbers. I figure, since I''m paying "New-Car" money on a lump of carbon, it''s pretty much a 100% emotional purchase (not meaning to sound like a chick here but its undeniable). And numbers to me pose emotive value, i.e. I feel uncomfortable knowing that, even if its just on paper, the stone is not tight enough. I''m sure I''m not alone here and I think vendors should understand this. Thats the sole reason why I''m not at a B&M, and instead here. My worst fear now is of unscrupulous vendors fudging sarin numbers.

Anyway sorry for the digression, back on topic. I''m finding this discussion interesting

 

[michaelgem]

I understand perfectly now (I think) why Paul said LGF% is meaningless by itself. This revelation actually got me curious: what then is the IDEAL LGF ANGLE? Its surprising since Paul states that LGF actually accounts for more surface area (undeniably true), yet consumers and vendors, even the smart ones here on PS, only assess MPF angles, without a mention of LGF angles. If MPF angles are ideally at 40.75, whats the ideal for LGF angles?

Thanks,
echelon6

echelon6

The Diamond Cut Accordance article may be the first formal addressing of your important question.

http://www.acagemlab.com/articles/sweetspot/index.html

Those of you who have read this recent Journal Article are aware that I devote a large section to
establishing why roughly 77% is the heart of the sweet spot of Ideal for this important,
second only to pavilion angle, dimension in round brilliant diamond cutting.



In the section “The importance of the length of the pavilion halves” I conclude by saying:

“This comparison of optical performance
and the previous one in Figure 8 support the
observation that an attractive balance between
the areas occupied by the pavilion mains and halves is
necessary for these two central reasons.

A number of individuals, diamond
manufacturers, and this investigator agree that
the best balance between the area of the main
reflections and the area of the halves is obtained
with a 75% to 80% length of the pavilion halves.

This is the sweet spot range of lower half length
that retains the large flash sparkle and fire and
at the same time provides a greater amount
of scintillation.

The range of possible GIA
'Excellent' lower girdle facet lengths is 70% to
85%. Both ranges have the same 77.5% as the
centre of the sweet spot of lower half length.

Prior to this conclusion are supporting discussions, photographs and DiamCalc photorealistic simulations.

Ideal regards,

Michael

PS I agree with Paul and others that LGF% is meaningless by itself. The reason it is second in
importance to pavilion angle is that this length indicates the amount of pavilion area occupied
by the halves compared to the area occupied by the mains.

Among my conclusions is the statement:

"Essential to the concept of
‘Ideal’ is the balance of the properties of
reflections from the pavilion main facets and
the pavilion halves (the lower girdle facets.)"

 

[echelon6]

Michael, taht sounds like a great read. Can I please have a link?

 

[Paul-Antwerp]

Date: 7/18/2007 12:20:21 AM
Author: strmrdr

Date: 7/17/2007 11:19:49 PM
Author: echelon6

A question for Paul and Garry (and everyone else):

I understand perfectly now (I think) why Paul said LGF% is meaningless by itself. This revelation actually got me curious: what then is the IDEAL LGF ANGLE? Its surprising since Paul states that LGF actually accounts for more surface area (undeniably true), yet consumers and vendors, even the smart ones here on PS, only assess MPF angles, without a mention of LGF angles. If MPF angles are ideally at 40.75, whats the ideal for LGF angles?

Thanks

good question.

Good question, but impossible to answer. The whole pavilion is essential in reflecting light upwards, both LGF''s and MPF''s.

Let us assume that there is an ideal angle for LGF''s. Can we then cut the pavilion with only 16 LGF''s and no MPF (thus LGF-% of 100%), thus maximizing light return? Maybe, but we would lose the contrast, added by the MPF''s, and also the size of virtual facets will probably go up, while number of virtual facets goes down. So, we are clearly losing in scintillation, which is a negative.

In the same way, as the difference in angle with LGF''s with MPF''s increases, the LGF-% goes down, which also means that the surface of the LGF''s decreases. It is an exercise with a number of variables to find some kind of ideal combination.

All in all, this just shows that one should look at all proportions together, and then leave some room for personal preference in the observation. There is no use in isolating one factor, and trying to find the best possible for that factor.

Live long,

 

[Paul-Antwerp]

Date: 7/17/2007 11:19:49 PM
Author: echelon6

A question for Paul and Garry (and everyone else):

I understand perfectly now (I think) why Paul said LGF% is meaningless by itself. This revelation actually got me curious: what then is the IDEAL LGF ANGLE? Its surprising since Paul states that LGF actually accounts for more surface area (undeniably true), yet consumers and vendors, even the smart ones here on PS, only assess MPF angles, without a mention of LGF angles. If MPF angles are ideally at 40.75, whats the ideal for LGF angles?

Thanks

And I misread the rest of the question.

The reason why the whole industry only mentions MPF''s, while they are a smaller part of the pavilion-surface, is historical. These angles are easier to measure, both with the old hand-tools of the beginning of the 20th century, as with shadow-measurement-tools like Sarin and OGI of the end of the 20th century.

Here is an analogy:

It is the start of the mussel-season in Belgium, I mean mussels from Zealand (Belgians are the world''s biggest consumers of both Zealand-mussels as French champagne). Mussels are sold per kilogram, and this weight is including the shells. Now, this year, because of weather conditions, each shell contains a lot more meat. Now, I have the problem that I cannot eat a full kilogram of mussels anymore, while I am still gaining weight. How can that be?

Live long,

 

[JohnQuixote]

Date: 7/18/2007 3:10:16 AM
Author: strmrdr

Date: 7/18/2007 2:03:33 AM
Author: JohnQuixote


77.5% is dead-center of the GIA EX range.
Knowing how human taste varies, I agree with that particular call. I'm trying to be Switzerland in the Strm/Wink wars here.

For the mature palate 75% vs 80% is a fine Cab vs a fine Shiraz. One's better with porterhouse, the other with ribeye (lighting condition comparison) but both have equal appeal and in a premium diamond will make you weep with joy. Also, like fine wine, many people wouldn't even notice the dif unless you pointed it out... Just that they're both firecrackers.

The data is groovy Strm. Thanks for doing that. One thing I'd add is that you're getting 1 fixed-face-up number... (Dave Atlas will be cool with just that info methinks, right Dave?)

...but what this means is that light-dark ratios at 0 degrees tilt are all that's being measured.

The AGSL metric is more telling in this case because they include light return values at 0 degress and tilted to 4 compass directions. Jim C from the lab has told me that inside robust t/c/p combos the values in cherry lower half % ranges equal out as soon as you move the diamond because the light-dark ratios reverse themselves. He's also said much of this is beyond our human cognitive ability to perceive (that for Wink, Alj and Belle) but we're already nano-spec-ing so I thought what the hey.

actually I have to disagree.
With a 75lgf% and a 80% lgf% stones of similar make in hand I could pick out the differences face up or tilted and at arm length they may be more apparent tilted than face up.
Because with min. head shadow the arrows didnt show as much face up as tilted.

You misunderstood Strm? I included the part of my post you omitted (wine vs shiraz). There are distinctions but in robust makes they are less significant.

Back on p1...

Date: 7/15/2007 12:12:18 PM
Author: diamondseeker2006

You know what I think? I think you are overanalyzing. I have one diamond with 80% lgf and two diamonds that have 75%. Honest to goodness, I just had to look up the numbers because off hand I could not have told you which was which. Yes, it may be a personal preference thing, but you have to realize if a stone is graded AGS0, then it has great light return. I have been guilty of overanalyzing the numbers in the past as well, so I understand...

DS is a discriminating consumer who gets way inside the numbers. She's no less discerning than any enthusiast and far more attentive than the average person. From experience I suspect that once she looked up the numbers she said "ok - that's logical..." because the subtleties between 5% are there but again... wine.

To be clear in what I was saying above - what Jim told me is beyond human cognitive ability is distinctions in generated quality values like x.xx vs y.yy that occur when comparing closely matched diamonds.

 

[echelon6]

Date: 7/18/2007 10:19:43 AM
Author: Paul-Antwerp

Date: 7/17/2007 11:19:49 PM
Author: echelon6

A question for Paul and Garry (and everyone else):

I understand perfectly now (I think) why Paul said LGF% is meaningless by itself. This revelation actually got me curious: what then is the IDEAL LGF ANGLE? Its surprising since Paul states that LGF actually accounts for more surface area (undeniably true), yet consumers and vendors, even the smart ones here on PS, only assess MPF angles, without a mention of LGF angles. If MPF angles are ideally at 40.75, whats the ideal for LGF angles?

Thanks

And I misread the rest of the question.

The reason why the whole industry only mentions MPF''s, while they are a smaller part of the pavilion-surface, is historical. These angles are easier to measure, both with the old hand-tools of the beginning of the 20th century, as with shadow-measurement-tools like Sarin and OGI of the end of the 20th century.

Here is an analogy:

It is the start of the mussel-season in Belgium, I mean mussels from Zealand (Belgians are the world''s biggest consumers of both Zealand-mussels as French champagne). Mussels are sold per kilogram, and this weight is including the shells. Now, this year, because of weather conditions, each shell contains a lot more meat. Now, I have the problem that I cannot eat a full kilogram of mussels anymore, while I am still gaining weight. How can that be?

Live long,

You know sometimes with you and Garry, its harder to understand the analogies than the underlying concept

 

[JohnQuixote]

Date: 7/18/2007 3:27:48 AM
Author: strmrdr
also thinking about this another issue with the AGS metric is one directional source of obstruction don''t match the real world.
On the finger there are many sources and direction of obstruction.
A painting on a white wall may be an obstruction in the green zone, someones shirt in the red, the person standing beside them in the green and red zones.

Which is why light source independence seems the way to go over direct measure and why tilting becomes even more important.

 

[JohnQuixote]

Date: 7/18/2007 3:56:25 AM
Author: Garry H (Cut Nut)

Not to mention the actual person looking at the diamond (perhaps the one constant factor?)?

It''s true that someone big causes more obstruction. Hey, as long as we''re at it maybe we can develop a height-weight reference chart for lower halves %? We could even have different cutouts in our showrooms...

"Excuse me sir, I think this diamond suits you better."
"But I like that other one."
"No no. You''re in the welterweight division, I''m afraid you''re restricted to these..."

 

[JohnQuixote]

Date: 7/18/2007 3:56:25 AM
Author: Garry H (Cut Nut)

And the orientation of the stone? Should it be tilted to 4 compass directions? (that is two different directions i think John?) And should those directions be at what angles for rounds and what about other shapes?

For software models 2 would do (depends on lighting scheme). For real models it''s tilted in 4 because no real model has perfect symmetry.

Wink may recall the amount of tilt (?) - it''s different for light performance assessment than it is for girdle reflection assessment.

 

[pyramid]

Date: 7/18/2007 10:19:43 AM
Author: Paul-Antwerp

Date: 7/17/2007 11:19:49 PM
Author: echelon6

A question for Paul and Garry (and everyone else):

I understand perfectly now (I think) why Paul said LGF% is meaningless by itself. This revelation actually got me curious: what then is the IDEAL LGF ANGLE? Its surprising since Paul states that LGF actually accounts for more surface area (undeniably true), yet consumers and vendors, even the smart ones here on PS, only assess MPF angles, without a mention of LGF angles. If MPF angles are ideally at 40.75, whats the ideal for LGF angles?

Thanks

And I misread the rest of the question.

The reason why the whole industry only mentions MPF's, while they are a smaller part of the pavilion-surface, is historical. These angles are easier to measure, both with the old hand-tools of the beginning of the 20th century, as with shadow-measurement-tools like Sarin and OGI of the end of the 20th century.

Here is an analogy:

It is the start of the mussel-season in Belgium, I mean mussels from Zealand (Belgians are the world's biggest consumers of both Zealand-mussels as French champagne). Mussels are sold per kilogram, and this weight is including the shells. Now, this year, because of weather conditions, each shell contains a lot more meat. Now, I have the problem that I cannot eat a full kilogram of mussels anymore, while I am still gaining weight. How can that be?

Live long,

Larger mussels' taking up more room in each shell means less shells by weight. Same as LGF angle they are difficult to measure amount of meat by surface area until you open the shell?

 

[michaelgem]

I understand perfectly now (I think) why Paul said LGF% is meaningless by itself. This revelation actually got me curious: what then is the IDEAL LGF ANGLE? Its surprising since Paul states that LGF actually accounts for more surface area (undeniably true), yet consumers and vendors, even the smart ones here on PS, only assess MPF angles, without a mention of LGF angles. If MPF angles are ideally at 40.75, whats the ideal for LGF angles?

Thanks,
echelon6

echelon6,

I hasten to point out as Paul and others have that LGF or half-length causes differences in appearance that in some acceptable sweet spot range are matters of individual taste.

For me that range is close to 75%-80%, while the GIA with their 70+ thousand comparisons testing found the range to be 70% to 85%. You can obtain AGS performance-based scores of Ideal 0 with lower half lengths over even a wider range.

Whatever tolerance range or sweet spot of half-length floats your boat, beyond that range, no matter how perfect the cut is otherwise, the diamond’s sparkle is perceived to be too splintery with mains that are too thin, and in the other direction perceived as too blocky or chunky and lacking in scintillation.

What the Accordance Article demonstrates by “direct assessment” is the logic behind the agreement as to the center of the sweet spot range of lower half length.

Close to 77% maximizes the properties we love in Ideal, the best brilliance, fire and sparkle, i.e. the best beauty.

Ideal regards,

Michael

 

[strmrdr]

Date: 7/18/2007 11:00:15 AM
Author: JohnQuixote

Date: 7/18/2007 3:56:25 AM
Author: Garry H (Cut Nut)

Not to mention the actual person looking at the diamond (perhaps the one constant factor?)?

It''s true that someone big causes more obstruction. Hey, as long as we''re at it maybe we can develop a height-weight reference chart for lower halves %? We could even have different cutouts in our showrooms...

''Excuse me sir, I think this diamond suits you better.''
''But I like that other one.''
''No no. You''re in the welterweight division, I''m afraid you''re restricted to these...''

hmmmm
even better....
cut just for you diamonds(tm) based on a picture and 27 point personality evaluation our cyborgs will cut the perfect diamond for you!

 

[Paul-Antwerp]

Michael,

On a totally different point.

The concept of a ''sweet spot'' being in the center of a lab''s top-range is for me contrary to the original article of Bruce Harding, where top-performers are always close to an area where performance suddenly drops.

Is there any proof that Mount Everest is at the center of the Himalaya-range?

Live long,

 

[JohnQuixote]

Date: 7/18/2007 11:09:58 AM
Author: strmrdr
hmmmm
even better....
cut just for you diamonds(tm) based on a picture and 27 point personality evaluation our cyborgs will cut the perfect diamond for you!

Excellent! Actually it''s funny you say that because I often tell people that judging a diamond by numbers is like reading data about a blind date...seeing actual images is like seeing a picture of her and getting the diamond in-hand is actually going on the date. The only way to know how she looks to your eye and if the personality is what you hoped for is to spend time with ''her.''

Thanks to PS people can get a sense for what they need - whether it be shape, color/clarity or make. In that sense the "matchmaker" test is not so different than what we try to do here. Just make sure people know that comparing the # of eyelashes between possible dates may be a little overkill.

 

[Cehrabehra]

Date: 7/18/2007 3:15:32 AM
Author: Garry H (Cut Nut)
the wine analogies always interest me John

Actually there is no way to answer which is ''ideal'' if you believe as a few of us do that ideal is a silly concept.

Ideal for who?
The ideal shiraz for me is too fruity and sweet for my best friend who prefers wines grown on cooler limestony soils that make me go uurgh!

Ideal is a bad term for diamonds too, but AGS have married themselves to it by using it for Princess cuts. An ideal princess cut is a poor mans ideal round.

So the ideal LG facet length or depth is an oxymoron for me because i know now for sure that there is a play off between fire and light return. Ideal for my wife is probably not ideal for my daughter.

That was why I inventd the term Firey Ideal Cut (FIC) and Brilliant Ideal Cut (BIC) but I am open to ideas for the better names for those

And I am much more of this thought as well Garry, though I am looking forward to a time when the flavors can be broken down further than just those two and I don''t know *how* but I really do feel that lgf personality times can and should be one type of further definition (as large vs small tables perhaps as well but I''ve digressed...)

I find "pinacle worship" to be interesting both in terms of finding the pinacle of pinacles as well as seeing how some people are really drawn to whatever pinacle is highest even if that difference is in the nanos. I am much more a believer in the multiple pinacle theory and those 10k image ASET charts back that up.

 

[Cehrabehra]

Date: 7/18/2007 8:34:49 AM
Author: echelon6
Keep in mind I''m all the way in Australia, and theres not a snowball''s chance in hell I''d get to sight the diamonds im considering prior to wiring money. If I''m buying sight unseen, the rock may as well be ''numberclean'' to me

I do enjoy looking at numbers. I figure, since I''m paying ''New-Car'' money on a lump of carbon, it''s pretty much a 100% emotional purchase (not meaning to sound like a chick here but its undeniable). And numbers to me pose emotive value, i.e. I feel uncomfortable knowing that, even if its just on paper, the stone is not tight enough. I''m sure I''m not alone here and I think vendors should understand this. Thats the sole reason why I''m not at a B&M, and instead here. My worst fear now is of unscrupulous vendors fudging sarin numbers.

Anyway sorry for the digression, back on topic. I''m finding this discussion interesting

Garry can''t mention it, but I can mention that Garry has a store out there I think in Melbourne.... so yeah you could find a place with a variety of ideal cut stones in australia!

 

[Cehrabehra]

Date: 7/18/2007 10:38:50 AM
Author: echelon6

Date: 7/18/2007 10:19:43 AM
Author: Paul-Antwerp

Date: 7/17/2007 11:19:49 PM
Author: echelon6

A question for Paul and Garry (and everyone else):

I understand perfectly now (I think) why Paul said LGF% is meaningless by itself. This revelation actually got me curious: what then is the IDEAL LGF ANGLE? Its surprising since Paul states that LGF actually accounts for more surface area (undeniably true), yet consumers and vendors, even the smart ones here on PS, only assess MPF angles, without a mention of LGF angles. If MPF angles are ideally at 40.75, whats the ideal for LGF angles?

Thanks

And I misread the rest of the question.

The reason why the whole industry only mentions MPF''s, while they are a smaller part of the pavilion-surface, is historical. These angles are easier to measure, both with the old hand-tools of the beginning of the 20th century, as with shadow-measurement-tools like Sarin and OGI of the end of the 20th century.

Here is an analogy:

It is the start of the mussel-season in Belgium, I mean mussels from Zealand (Belgians are the world''s biggest consumers of both Zealand-mussels as French champagne). Mussels are sold per kilogram, and this weight is including the shells. Now, this year, because of weather conditions, each shell contains a lot more meat. Now, I have the problem that I cannot eat a full kilogram of mussels anymore, while I am still gaining weight. How can that be?

Live long,

You know sometimes with you and Garry, its harder to understand the analogies than the underlying concept

I love their analogies! Esp John LOL Only the girls appreciated my big butt analogy!! LOL

 

[Cehrabehra]

Date: 7/18/2007 11:07:21 AM
Author: michaelgem

I hasten to point out as Paul and others have that LGF or half-length causes differences in appearance that in some acceptable sweet spot range are matters of individual taste.

Whatever tolerance range or sweet spot of half-length floats your boat, beyond that range, no matter how perfect the cut is otherwise, the diamond’s sparkle is perceived to be too splintery with mains that are too thin, and in the other direction perceived as too blocky or chunky and lacking in scintillation.

I think the ends of the lgf range can be attractive too so I''m not sure I agree with the use of "too" here. Dee Jay''s diamond is I think over 90 and while it has a unique look to it, there''s no doubt it is gorgeous... of course it is huge and IMO big diamonds can "get away with" longer lgf easier than small diamonds.... but my personal taste is there is (almost) no such thing as too blocky or chunky and giving up some scintillation for that is MORE than a fair trade! I know I''m not alone in that.

 

[JohnQuixote]

Date: 7/18/2007 12:23:56 PM
Author: Cehrabehra

I love their analogies! Esp John LOL Only the girls appreciated my big butt analogy!! LOL

I chuckled but kept silent after Wink started talking about going shopping with the guys. While Wink is pants shopping and I'm saying creepy hot tub stuff, Paul is eating mussels & dreaming about Garry... Meanwhile Garry is being the tame one! (?) Who would have guessed it?

 

[Ellen]

Date: 7/18/2007 12:45:41 PM
Author: JohnQuixote

Date: 7/18/2007 12:23:56 PM
Author: Cehrabehra

I love their analogies! Esp John LOL Only the girls appreciated my big butt analogy!! LOL

I chuckled but kept silent after Wink started talking about going shopping with the guys. While Wink is pants shopping and I''m saying creepy hot tub stuff, Paul is eating mussels & dreaming about Garry... Meanwhile Garry is being the tame one! (?) Who would have guessed it?

LOL!!!

 

[WinkHPD]

Date: 7/18/2007 3:10:16 AM
Author: strmrdr

With a 75lgf% and a 80% lgf% stones of similar make in hand I could pick out the differences face up or tilted and at arm length they may be more apparent tilted than face up.
Because with min. head shadow the arrows didnt show as much face up as tilted.

Ah, I am probably answering after it has already been answered, since there are 8,000 posts now to read after I thought this thread had been put to bed...

What John is referring to is the large apparent drop in light return that you show with your two examples. What John is saying is that as you rotate the stone that the dark areas become light and the light dark, resulting in the sparkle that we all love so much. When these dark areas turn bright you will have MORE light return than with the 80% lgfs, and that the differences will either balance or come close to balancing and Jim Caudill from AGS is stating that the apparent differences in brightness are beyond human recognition.

No one is saying that you will not be able to see the different flavor of the longer/shorter LGF''s, just not be able to accurately detect which is brighter.

Wink

 

[WinkHPD]

Date: 7/18/2007 3:23:04 AM
Author: Maisie


I got into a complete spin last week when I realised my new diamond has a HCA score of .6 - I actually almost cancelled it. Its going to be on its way soon and I am sure I will love it. If I don''t - well at least I have seen it with my own eyes and made a decision based on what I saw instead of what I read.

LOL! I made a large purchase a couple of years ago of some GIA papered stones that had a lot of stones in the >1 ranking on HCA. I was ecstatiic that they ranked so well, then someone started commenting on how they did not like stones less than 1 and now there is a stigma to my beautiful stones because someone did not like them.

HOOEY! Pigswollop!

It is one of the reasons I fight so hard when someone tries to impose their taste as the norm. There are LOTS of tastes and all of them are valid. An AGS 0 will be a beautiful stone, it may come in several flavors, but it will be beautiful.

Wink

 

[Cehrabehra]

Date: 7/18/2007 12:45:41 PM
Author: JohnQuixote

Date: 7/18/2007 12:23:56 PM
Author: Cehrabehra

I love their analogies! Esp John LOL Only the girls appreciated my big butt analogy!! LOL

I chuckled but kept silent after Wink started talking about going shopping with the guys. While Wink is pants shopping and I''m saying creepy hot tub stuff, Paul is eating mussels & dreaming about Garry... Meanwhile Garry is being the tame one! (?) Who would have guessed it?

this is VERY true LOL omg I could go off in so many directions here... but.... I.... will.... refrain....

 

[Lorelei]

Date: 7/18/2007 1:13:24 PM
Author: Wink

Date: 7/18/2007 3:23:04 AM
Author: Maisie


I got into a complete spin last week when I realised my new diamond has a HCA score of .6 - I actually almost cancelled it. Its going to be on its way soon and I am sure I will love it. If I don't - well at least I have seen it with my own eyes and made a decision based on what I saw instead of what I read.

LOL! I made a large purchase a couple of years ago of some GIA papered stones that had a lot of stones in the >1 ranking on HCA. I was ecstatiic that they ranked so well, then someone started commenting on how they did not like stones less than 1 and now there is a stigma to my beautiful stones because someone did not like them.

HOOEY! Pigswollop!

It is one of the reasons I fight so hard when someone tries to impose their taste as the norm. There are LOTS of tastes and all of them are valid. An AGS 0 will be a beautiful stone, it may come in several flavors, but it will be beautiful.

Wink

Thank you for that wee nugget Wink - pigswallop - I have never heard that one before, brilliant!

I also must say, I have enjoyed you chaps on this thread with your collective witticiscms!

 

[Paul-Antwerp]

Date: 7/18/2007 1:13:24 PM
Author: Wink

Date: 7/18/2007 3:23:04 AM
Author: Maisie


I got into a complete spin last week when I realised my new diamond has a HCA score of .6 - I actually almost cancelled it. Its going to be on its way soon and I am sure I will love it. If I don''t - well at least I have seen it with my own eyes and made a decision based on what I saw instead of what I read.

LOL! I made a large purchase a couple of years ago of some GIA papered stones that had a lot of stones in the >1 ranking on HCA. I was ecstatiic that they ranked so well, then someone started commenting on how they did not like stones less than 1 and now there is a stigma to my beautiful stones because someone did not like them.

HOOEY! Pigswollop!

It is one of the reasons I fight so hard when someone tries to impose their taste as the norm. There are LOTS of tastes and all of them are valid. An AGS 0 will be a beautiful stone, it may come in several flavors, but it will be beautiful.

Wink

A complete side-note, but all Infinity-rounds have a HCA-score close to 0.5

We consider it a proof that, if you know what you are doing, you can really go closer to the limit.

Live long,