Wriggle Room in Paul Gias Ideal Proportions ?

[Texas Leaguer]

bmfang,
Super ideal cuts are not yet a commodity here in the States. Not by a long shot! Cutting has gotten much better over the last several years, but true precision cut diamonds are still quite rare relative to the broader market.

Though I do agree that Octavias are even rarer

 

[bmfang]

bmfang,
Super ideal cuts are not yet a commodity here in the States. Not by a long shot! Cutting has gotten much better over the last several years, but true precision cut diamonds are still quite rare relative to the broader market.

Though I do agree that Octavias are even rarer

I stand corrected @Texas Leaguer. Though from my perspective, the US market has a much greater awareness of superideals than the Australian market does IMHO.

 

[Texas Leaguer]

I stand corrected @Texas Leaguer. Though from my perspective, the US market has a much greater awareness of superideals than the Australian market does IMHO.

That may be true. And you also may get that sense monitoring this forum. People with a keen interest in cut quality tend to find their way here as a result of their research. You won't find this much diamond knowledge concentrated in any other space on the internet. And people are going to the internet for in-depth information because most brick and mortar retailers are not providing it.

 

[drk14]

Oh god..., what will happen if the world was filled with super ideal Cut Diamonds?

Anyone thinks it will become the next generic? Or is it already?

Maybe this is off-topic, but do you think there will come a time when technological advances will permit the automation of cutting of super-ideal diamonds, which could make them "generic", in a sense? Will the diamond connoisseurs then begin to prefer some type of more exclusive, non-ideal cut?

Just thinking out loud, feel free to ignore...

 

[gm89uk]

Nice discussion, thanks Texas Leaguer and Rockdiamond.

@Rockdiamond, you did not agree that AGS0 would be the type you love, what range are the proportions of the 60:60s you like? What's your 60:60 'cheat sheet'?

 

[Texas Leaguer]

Maybe this is off-topic, but do you think there will come a time when technological advances will permit the automation of cutting of super-ideal diamonds, which could make them "generic", in a sense? Will the diamond connoisseurs then begin to prefer some type of more exclusive, non-ideal cut?

Just thinking out loud, feel free to ignore...

The technology is already available to permit widespread cutting of super-ideal diamonds. Yes it takes more skill and the best equipment, but those upgrades are very doable. It's more a philosophical/strategic/economic issue. Manufacturers still must be competitive and concerned with their bottom line. So long as the market is rewarding cutting for weight over cutting for beauty, they will be following suit. It is changing, but rather slowly. Status quo has historically been very strong in the diamond business.

 

[diagem]

The technology is already available to permit widespread cutting of super-ideal diamonds. Yes it takes more skill and the best equipment, but those upgrades are very doable. It's more a philosophical/strategic/economic issue. Manufacturers still must be competitive and concerned with their bottom line. So long as the market is rewarding cutting for weight over cutting for beauty, they will be following suit. It is changing, but rather slowly. Status quo has historically been very strong in the diamond business.

I don't believe manufacturers are deliberately cutting for weight, they have a (GIA) range they must adhere to for a safe and comfortable landing. I call it the cutters "comfortable numbness zone". Manufacturers truly believe they are manufacturing cut for beauty Diamonds. Before GIA cut grade you could say weight retention was the main objective but now their cutting range has significantly narrowed so they are not really cutting for weight anymore. On the other hand, cutting for high precision optical symmetry (you for some reason chose the word beauty) is a whole different ballgame. Cutters need to know what to aim for in this case. Most cutters have no clue about ray tracing technology or its purpose. They are really clueless on the subject and worse off, they are not even willing to learn, it actually scares them.

 

[Rockdiamond]

Nice discussion, thanks Texas Leaguer and Rockdiamond.

@Rockdiamond, you did not agree that AGS0 would be the type you love, what range are the proportions of the 60:60s you like? What's your 60:60 'cheat sheet'?

My pleasure and it's absolutely amazing to revive this topic after all these years- it's a new and different discussion than it was before.
My version of the "cheat sheet".....
Know the best cutters.
Remember, we don't buy ( or list on our site) paper, we buy real live diamonds- unlike 95% of online diamond sellers.
Because our business model is different- and my training- I thoroughly examine diamonds, but rarely look at the CA/PA #'s.
Consider the pragmatic reasons. When I'm looking for a diamond it's rarely a 1ct G/SI1- rather we look for the unique items.
If I see a 6ct eye clean K/SI2 I'm not going to reject it based on ca/pa unless I see a visual deficiency. In which case I don't look at ca/pa #'s either- I simply reject and move on.
The argument has been raised- since I buy in a totally different manner than internet shoppers, my "use your eyes" argument is invalid.
But from my perspective, looking at which real diamonds get eliminated using these narrow parameters is a HUGE disadvantage to consumers.
For one thing- consider people who read this forum and buy in person.
A seller who knows great make- and is showing the client stones with "pure" motivation of trying to do right by the client will be looked at as "trying to pull something" if they suggest a stone outside these narrow parameters. Or a stone that scores 3 on HCA, and the seller never even heard of HCA.
So what happens is that, in effect, consumers are told- forget what your eyes say, use this chart.
Then we have the people who own diamonds they love- till they find out they're "off the chart" which makes them second guess a purchase, in many cases needlessly.
I'm not arguing in favor of badly cut stones by any means.
Rather that the method of picking a great stone is hampered by parameters that are overly restrictive.
Last point- my intention was not to imply that I would not love a diamond graded 0 by AGS for that reason alone.
There've certainly been cases that I chose a diamond which had stats within the list which is the subject of this thread over a 60/60.
Hard and fast rules rarely work in the real world. There's just too many shades of gray.

 

[Rockdiamond]

I don't believe manufacturers are deliberately cutting for weight, they have a (GIA) range they must adhere to for a safe and comfortable landing. I call it the cutters "comfortable numbness zone". Manufacturers truly believe they are manufacturing cut for beauty Diamonds. Before GIA cut grade you could say weight retention was the main objective but now their cutting range has significantly narrowed so they are not really cutting for weight anymore. On the other hand, cutting for high precision optical symmetry (you for some reason chose the word beauty) is a whole different ballgame. Cutters need to know what to aim for in this case. Most cutters have no clue about ray tracing technology or its purpose. They are really clueless on the subject and worse off, they are not even willing to learn, it actually scares them.

THANK YOU!! I have a lot of respect for Bryan- but we seem to butt heads a lot.
This particular issue is one reason.
I don't think there a bunch of greedy guys sitting around saying, "Let's cut some ugly pos, and save 10% weight"
Ugly diamonds are a lot harder to sell. In fact, you'd probably need to reduce the price to sell it.
Eventually, a person will need to buy the diamond, and the vast majority of buyers have the ability to see.
Please let's clarify these motivations because many times such incorrect sentiment is used to insult people who may be cutting lovely diamonds. Also many times this false motivation is used to insult diamonds.
Even in Fancy Shapes- where there's no GIA cut grade, I have noticed a vast improvement in cutting quality over the past 10 years- so it's not only the GIA cut grade.
No cutter can ignore yield- on the other hand, if that's their main motivation they will NOT produce saleable diamonds.

 

[Texas Leaguer]

I don't believe manufacturers are deliberately cutting for weight, they have a (GIA) range they must adhere to for a safe and comfortable landing. I call it the cutters "comfortable numbness zone". Manufacturers truly believe they are manufacturing cut for beauty Diamonds. Before GIA cut grade you could say weight retention was the main objective but now their cutting range has significantly narrowed so they are not really cutting for weight anymore. On the other hand, cutting for high precision optical symmetry (you for some reason chose the word beauty) is a whole different ballgame. Cutters need to know what to aim for in this case. Most cutters have no clue about ray tracing technology or its purpose. They are really clueless on the subject and worse off, they are not even willing to learn, it actually scares them.

I'll go with that explanation. It's not that they don't think they are making beautiful diamonds by cutting to GIA EX. I'm sure they do. By having a cut quality target today that rewards them financially, whereas before GIA cut grading they really had few qualitative constraints, cutting of rounds in general has improved dramatically. I'm sure most manufactures think it is plenty good enough. But they are definitely cutting to the margins of the EX range to retain weight where possible. Especially around magic carat marks, which are in and of themselves the rather arbitrary and traditional motivators for leaving stones as heavy as possible. A manufacturer cannot be expected to take even a few points off to improve a stone if they will be penalized by the market for doing so.

To go back to the analogy board, if you are a fan of good tequila you probably prefer those made of 100% blue agave cactus. The silver is right out of the still and it makes margaritas that are plenty good. But if you have developed your pallette and like to savor tequila by sipping it and getting the full flavor and effect, you probably prefer a reposado or anejo. This is the silver that has been further refined and processed by aging in oak barrels. It takes longer and costs more.

So, while a good silver ain't bad for mixing, it's wonderful that some manufactures also offer tequilas that have been specially crafted for those who have learned to appreciate the difference.

 

[Rockdiamond]

Bryan- the issue of 1.00 stones being badly cut used to be far more prevalent.
We may find some overly deep 1.00's that just make the 1.00 mark, but many still look ok. Small, but pleasant appearance. Back in the old days, 10 years ago- you'd see all sorts of weird looking 1.00ct stones mixed in with better cuts. There may still be plenty of these funky looking stones if you peruse stones with "Good" or Fair GIA cut rating. Which I have not done. But this jibes with Yoram's point that the cut grade did raise the overall bar with regard to weight retention. It definitely still goes on, but it's less of an impact on "light performance". Yes, we can find doggie GIA EX stones, but they are the exception. Based on the market I see here in NY- many cutters have gotten much better.
I could make the case that the GIA RBC cut grade is partly responsible for the increase of average fancy shape cutting over the past 10 years. The largest cutters of RBC's cut fancy shapes as well, so upping their game on RBC's spilled over to Fancy Shapes.
Of course, this is just a theory, Yoram can probably tell us why I'm wrong

Can we separate two issues of badly cut, and super ideal diamonds please?
1) "Super Ideal" diamonds are not common. It takes a lot of specific skills, and commitment to make them happen. We all agree- this is not a "common" way of cutting a diamond. As Yoram wrote, most cutters have no idea about ray tracing. I and many others will gladly pay more for a stone cut to these exacting standards by the best diamond cutters.
2) If stones are not attempting to be Super Ideals, there's different goals. There can be stones which are remarkably well cut that are not super ideal diamonds. Stones that might also be cut to the same high standards of super ideal. Those too, are also very rare.
So not all stones which are not Super Ideal are badly cut- and indeed, an argument can be made that stones with different LP goals can also be super well cut.
Again- that's why this list is so bad for consumers. It reinforces deeper stones while cutting out all the spready ones, such as 60/60. It's great for cutters though.
Plus, once we consider what appeals to people who love diamonds, we know that people love all kinds of shapes.
Stands to reason that at least a few different flavors of well cut RBC's will find fans.
Just as Jeff Beck and Geoge Benson do. ( I wasn't getting that tequila analogy- I'm not a drinker.... can we please stick to musical analogies

 

[Garry H (Cut Nut)]

I'll go with that explanation. It's not that they don't think they are making beautiful diamonds by cutting to GIA EX. I'm sure they do. By having a cut quality target today that rewards them financially, whereas before GIA cut grading they really had few qualitative constraints, cutting of rounds in general has improved dramatically. I'm sure most manufactures think it is plenty good enough. But they are definitely cutting to the margins of the EX range to retain weight where possible. Especially around magic carat marks, which are in and of themselves the rather arbitrary and traditional motivators for leaving stones as heavy as possible. A manufacturer cannot be expected to take even a few points off to improve a stone if they will be penalized by the market for doing so.

Nonsense Bryan and Yoram.
Cutters clearly chase the highest yields within each of GIA's grades.
For e.g. I just ran 1ct G VS2 XXX on RapNet. 140 stones with diameters smaller than 6.4mm (they ranged from -4% to -9% smaller diameters than the optimum 6.47mm), 45 in the sweet range of 6.41 to 6.5mm and 8 stones with larger than 6.5mm spreads.
Cutters use very sophisticated systems to ensure they squeeze out the best number of magic weights and top GIA grades. Always!
If i relaxed the GIA XVX then the results would have been worse!

 

[Garry H (Cut Nut)]

The smallest of those GIA XXXs is the correct diameter of a 0.93ct stone.
AND
We all know the 0.93ct stone would look 10% larger than the badly cut GIA XXX
So, well, maybe things are better than the bad'ol days. But please do not give GIA credit as the great salvation G-d.

 

[Rockdiamond]

Do you want to talk rare?
Do a search for 1.00ct
60 table/60 depth
D-J color
Any clarity
EX cut grade VG-EX Pol/Sym
I found.....45 diamonds worldwide.
Every single one was between 6.44-6.51 mm

take out the table and depth restrictions, you get about 13,000 results.
I guess making a comparison video won;t be that easy after all.....

 

[Rockdiamond]

The smallest of those GIA XXXs is the correct diameter of a 0.93ct stone.
AND
We all know the 0.93ct stone would look 10% larger than the badly cut GIA XXX
So, well, maybe things are better than the bad'ol days. But please do not give GIA credit as the great salvation G-d.

Interesting position Garry- to be clear- are you saying GIA's cut grade had no positive impact on overall cut quality?
Without a doubt, your work has certainly had a positive impact. As has Yoram's.
A lot of things have helped.
Not that I'm comparing GIA to the Allmighty- but they have been a positive force IMO

 

[Garry H (Cut Nut)]

David David David.
Stats, lies and DAMM lies.
Search for a spread of depth 1ct any any 59.5 to 60.5 and there are 532 GIA X, X to VG
Same crieteria 57% table 61% depth = 7 stones.

 

[Rockdiamond]

Garry Garry Garry....hey buddy
If we're looking at a given style of cutting, then ok, round it off. Back in the day, before we actually knew who the other guy was, this whole thing crystallized into 60/60 vs whatever....and 60/60 became, here on PS, a certain type of cutting style that includes a narrow range of numbers near 60%.
But if I want a 60/60, I want 60/60.
What if a cutter does what it takes to get to the exact 60'60 number?
Kind of like it's own "super ideal"
Who's trying to get to an exact number of 57% table 61% depth?
Not to re-open any arguments of the old days, it's a moot point nowadays.
60/60 lost

 

[Garry H (Cut Nut)]

Garry Garry Garry....hey buddy
If we're looking at a given style of cutting, then ok, round it off. Back in the day, before we actually knew who the other guy was, this whole thing crystallized into 60/60 vs whatever....and 60/60 became, here on PS, a certain type of cutting style that includes a narrow range of numbers near 60%.
But if I want a 60/60, I want 60/60.
What if a cutter does what it takes to get to the exact 60'60 number?
Kind of like it's own "super ideal"
Who's trying to get to an exact number of 57% table 61% depth?
Not to re-open any arguments of the old days, it's a moot point nowadays.
60/60 lost

OK, but 57% table is rarer hahahahaha - and your logic is flawed anyway because 60% is rounded from 59.51 to 60.49% so your depths would have been badly matched
as in - game set and match David.
Please give up, or you will just ebd up hating me

 

[Rockdiamond]

I can't imagine that happening....the hate thing.
But there's two separate issues.
Yes, 60/60 lost in terms of what's the most popular, based on what's being cut.
But the issue of appearance, and what's "better" won't ever be solved- hence a thread like this.

To your point of rounding : Depth can be measured to the .01mm- so 60% depth is not rounded ( more accurately than .01mm. anyway)
- ok, so let's say the precision necessary to get the table between 59.51 and 60.49.

I can usually call a table within a point by eye. I'll bet you can too Garry.

it really is tons more fun when we discuss this without the old animosity.

 

[Garry H (Cut Nut)]

I am pretty good at that parlour game too. First time I met Martin Rap in early 1990's, he handed me a few stones and asked me to estimate proportions. He was one of the first to label me Cut Nut
But I can only get to about + or - 1%. Without measuring these - what do you eastimate the table sizes David? Anyone else can play too

 

[Dancing Fire]

David David David.
Stats, lies and DAMM lies.
Search for a spread of depth 1ct any any 59.5 to 60.5 and there are 532 GIA X, X to VG
Same crieteria 57% table 61% depth = 7 stones.

Even less as the table get smaller?

 

[Rockdiamond]

Even less as the table get smaller?

even more as the diameter gets smaller
DF- I have adored stones with table size of 50%. Talk about rare.

Cool game Garry.
Much different from guestimating with an actual diamond, but I'll play. 56% on the top one? 59 on the bottom.
Remember, it's late here.......

 

[Garry H (Cut Nut)]

Both 60% exactly David.
One with 40% star the other 65%

 

[Rockdiamond]

So I'm batting 500 if we're allowing 1% variance.
Not bad.
Tricky from the computer diamonds.....

 

[Rockdiamond]

Anyone care to hazard a guess on either of these?

 

[gm89uk]

Why not top 57 or 56 table with 34/41 and 80LGF 55 stars

Lower 57/56 table with 33/41.2 due to larger table reflection and 82 to 85 LGF.

 

[diagem]

Nonsense Bryan and Yoram.
Cutters clearly chase the highest yields within each of GIA's grades.
For e.g. I just ran 1ct G VS2 XXX on RapNet. 140 stones with diameters smaller than 6.4mm (they ranged from -4% to -9% smaller diameters than the optimum 6.47mm), 45 in the sweet range of 6.41 to 6.5mm and 8 stones with larger than 6.5mm spreads.
Cutters use very sophisticated systems to ensure they squeeze out the best number of magic weights and top GIA grades. Always!
If i relaxed the GIA XVX then the results would have been worse!

Nonsense Garry? Am I really making "no sense" to you?
Do you really believe cutters today don't think they conquered the top echelon even when they achieve a 1.00 carat <6.40mm triple X?? What I am witnessing is once they achieve the GIA cut grade stamp of approval they genuinely believe the mastered their craft, really!!
Sure Garry there are different pockets of greater demand for spreader stones but as far as their achievement, they achieved completing a top cut!!
Garry, you must remember that until GIA's cut grade if you hypothetically could have searched for the <6.40mm diameters you would have found a high percentage of 5.8-5.9mm 1.00+ carat rounds, I didn't search but it would be hard to believe you would find any today?

 

[Rockdiamond]

Yoram I do remember looking through parcels of Indian cut carat size stones and all were below 6mm.
That was years ago- lately Indian stones are far better cut on average.
Garry- if for no other reason than GIA dominates the market, even if the cut grade is not as stringent as you and many others here wanted- it's been a rising tide that lifted all boats. As well as other events and developments but still GIA has helped.
Peace guys. Please everyone stay off twitter about this

 

[Karl_K]

Define best.
For many(most/all) cutters the best diamond is one that combines high saleability with profitable yields.
GIA EX has raised the bar on the proportion sets for high salability just not to the level that makes many cut nuts happy.

 

[Texas Leaguer]

For many(most/all) cutters the best diamond is one that combines high saleability with profitable yields.
GIA EX has raised the bar on the proportion sets for high salability just not to the level that makes many cut nuts happy.

I agree Karl. And nobody should have a problem with that. It greatly improved the overall pool of diamonds for the consumer, while at the same time allowing manufacturers who want to serve that segment looking for the 'best of the best' to do so.

It is not necessary to force everyone to drink the very best tequila.