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50% of Modern Round Brilliants Cut Today would be Considered Super-Ideal 10-20 Years Ago

Rockdiamond

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I need to correct a few points I've made. ( I had long discussion with an amazing cutter friend)
Scanner technology has indeed improved over the past 20 years, allowing a greater degree of precision. Therefore it's possible that the best cut stones of 20 years ago might not make super ideal.
The result is greater consistency in look.
If we took 10 LK stones from the 80's and lined them up ( all same color, clarity and carat weight) we might be able to pick out very subtle differences stone to stone.
If we lined up 10 super ideals in the same test- a well trained observer probably could not pick out differences. Also need to point out that depending on the size of the diamond, most observers will NOT be able to detect differences in precision.
Plus, this does not mean people will prefer the super ideal to the LK btw.....
 

HDer

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If we took 10 LK stones from the 80's and lined them up ( all same color, clarity and carat weight) we might be able to pick out very subtle differences stone to stone.

Would these subtle differences manifest in lower GIA cut scores or higher HCA scores?
 

Rockdiamond

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Would these subtle differences manifest in lower GIA cut scores or higher HCA scores?

No. Other factors might impact HCA or GIA Cut grade- but the differences I'm talking about are far more subtle than either GIA or HCA
 

OoohShiny

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I need to correct a few points I've made. ( I had long discussion with an amazing cutter friend)
Scanner technology has indeed improved over the past 20 years, allowing a greater degree of precision. Therefore it's possible that the best cut stones of 20 years ago might not make super ideal.
The result is greater consistency in look.
If we took 10 LK stones from the 80's and lined them up ( all same color, clarity and carat weight) we might be able to pick out very subtle differences stone to stone.
If we lined up 10 super ideals in the same test- a well trained observer probably could not pick out differences. Also need to point out that depending on the size of the diamond, most observers will NOT be able to detect differences in precision.
Plus, this does not mean people will prefer the super ideal to the LK btw.....
haha I was just about to post to ask about the fact that @diagem has posted previously to say scanner technology is (obviously) always the best it can be at that moment in time, but that he's having to manually tweak the Octavias because the machines aren't accurate enough to deliver the required consistency lol
 

Serg

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Ah, I see.
I believe you've got the wrong impression.
The best cutters of 20 years were able to cut with the same precision as today, based on the technology.
Increases in technology have made it easier for lesser skilled cutters to achieve the precision of the best cutters- and improve yeild.

Have you ever compared a super ideal to a stone cut 20 years back in person?

Current Bruting systems( EOS and Laser bruting), scanners are much better than 20 years ago.
Most probably Planetary Mill is also better.
All its together helps a lot to cut round and specially fancy cuts with higher accuracy than 20 years ago.
Structure lights( as FS, IS, ASET, H&A) also improved cut symmetry .
Avalon+ helps improve polishing quality.
 

msop04

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To your first point: the best cut stones of 20 years ago would make super ideal.
Just because a diamond has a new GIA report does not mean it was cut yesterday.
As far as maximizing weight: This IS an area where technology has made a big difference- because people that are not extremely skilled can cut stones that are well cut.
So from my perspective, badly cut stones were indeed more common 20 years back. They were ( and are) easy to spot.


To the second point: If you buy a Super Ideal from a dealer, they are going to offer advantages a private seller can not- so it's really not the same deal for the buyer- even if it's the same stone.

Price: if you find a buyer that knows the selling points of what we're calling "Super Ideal" on the secondary market, yes, you could probably get a better price ( but nowhere near the retail price)
BUT- a tiny percentage of shoppers on the secondary market have this understanding.

Agreed on the first point... but as you've already mentioned, the "best cutters" and "best cuts" of 20 years ago are few and far between.

Regarding the ACA point. I'm not referring to what any vendor or seller can give the buyer, such as upgrades or whatever... vs. what a private seller can offer on a pre-loved stone. My point is that the super ideal cut diamond is still a super ideal, regardless of who is buying or selling. Whether or not a second buyer appreciates this is irrelevant. Those who can appreciate the precision and are willing to pay more will do so. :) Also, private sellers (not vendors) for pre-loved diamonds can't and don't expect to get the full retail price, regardless of the cut of a diamond.
 

flyingpig

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Rockdiamond

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Current Bruting systems( EOS and Laser bruting), scanners are much better than 20 years ago.
Most probably Planetary Mill is also better.
All its together helps a lot to cut round and specially fancy cuts with higher accuracy than 20 years ago.
Structure lights( as FS, IS, ASET, H&A) also improved cut symmetry .
Avalon+ helps improve polishing quality.
Thanks Serg- for pointing to the specifics.
The overall advances have clearly upped the game- the average fancy shape cut today is way better than the average stone cut 20 years ago.
But the overall average is a different discussion than the cream of the crop of 20 years ago versus the best cut today.
I'll concede that advances in cutting technology, combined with the advanced imaging and scanning technology make it possible to both cut, and distinguish the cream of the crop of 20 years ago versus the cream of the crop today.
Serg- would you say that the best examples from the best cutters of round diamonds 20 years back would make GIA triple EX today?
 

Rockdiamond

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Regarding the ACA point. I'm not referring to what any vendor or seller can give the buyer, such as upgrades or whatever... vs. what a private seller can offer on a pre-loved stone. My point is that the super ideal cut diamond is still a super ideal, regardless of who is buying or selling. Whether or not a second buyer appreciates this is irrelevant. Those who can appreciate the precision and are willing to pay more will do so. :) Also, private sellers (not vendors) for pre-loved diamonds can't and don't expect to get the full retail price, regardless of the cut of a diamond.
Yes, I couldn't agree more.
 

HDer

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Does anyone know what proportion of stones cut today are GIA triple ex? Is it over 50% by now?
 

John P

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Does anyone know what proportion of stones cut today are GIA triple ex? Is it over 50% by now?
From RapNet data in June: GIA graded RBs for sale, 0.30ct-3.00ct.
EX 68% (3X 56%)
VG 24%
GD 7%
FR 0.9%
PR 0.1%
 

HDer

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From RapNet data in June: GIA graded RBs for sale, 0.30ct-3.00ct.
EX 68% (3X 56%)
VG 24%
GD 7%
FR 0.9%
PR 0.1%

Thanks! This brings to mind an interesting question. Let's forget about super ideals vs 3X for a second here. Let's talk EX vs VG. Even I would be unwilling to recommend a VG stone for fear of being roundly criticized by every single member of this forum. But presumably if someone offered to trade me a VG 4 carat for a 3X 2 carat I should take the trade right? So there has to be some point at which it makes sense to go with the bigger VG stone. But how do we quantify where that is? Has anyone measured what the actual difference in light output, percentage wise, is between a VG and EX stone?

EDIT to not create another post: So from these numbers and what @Serg said it can be extrapolated that half or more of 3X stones on the market could be considered among the best of the best a decade or two ago. That's actually not that hard to believe.
 
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gm89uk

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HDer, I would say that as you go down in cut quality, there are wider tolerances. Actually some GIA VG stones have been recommended here before, although rarely. It's almost impossible to answer your question because just as there large differences in 'light output' between GIA X, there are even wider differences between VG.

That is because reporting labs like GIA and AGS will have strict cut offs, but people can own 40.4 pavilion angles coupled with a steeper crown that have excellent performance but are outside the tolerance of GIA X (for various reasons) etc, or if they had a very thin/thick girdle or they could just be total dogs.

For me it would be (all things being equal) if the cost of recutting (financially and in carat weight) 4ct VG into a well performing stone, would be leave me with a significantly larger stone than my original trade in; but this is not a real life situation that happens often, as carat remains the primary driver of cost.
 

John P

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Has anyone measured what the actual difference in light output, percentage wise, is between a VG and EX stone?
That's a logical question, but the system isn't so structured. The GIA system was based on sampled human observations which are rather diverse. Diamonds that qualify for GIA EX span a range of AGS0-AGS5 in terms of measurable brightness. But there are GIA VG diamonds capable of scoring AGS0.

...presumably if someone offered to trade me a VG 4 carat for a 3X 2 carat I should take the trade right?
Don't do it. Let's recut your 4 carat duck into a 3 carat masterpiece. ;-)
 

flyingpig

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Thanks!Let's talk EX vs VG. Even I would be unwilling to recommend a VG stone for fear of being roundly criticized by every single member of this forum.
Buying a VG cut can be a reasonable choice. I won't criticize you. But when you recommend a VG stone, just make sure you fully understand GIA cut grading system, clearly explain why the stone is graded VG cut, what the buyer is potentially missing, and what the risks are.
 

Karl_K

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What is really fascinating is to talk to someone like Paul or Yoram about precision cutting.
While tools certainly do play a part, what they will talk about most is process.
That is where cut grading has helped, it pushed more companies to pay attention and have better control over their process even if the are cutting steep/deep gia EX stones.
 

Serg

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Thanks Serg- for pointing to the specifics.
The overall advances have clearly upped the game- the average fancy shape cut today is way better than the average stone cut 20 years ago.
But the overall average is a different discussion than the cream of the crop of 20 years ago versus the best cut today.
I'll concede that advances in cutting technology, combined with the advanced imaging and scanning technology make it possible to both cut, and distinguish the cream of the crop of 20 years ago versus the cream of the crop today.
Serg- would you say that the best examples from the best cutters of round diamonds 20 years back would make GIA triple EX today?

David,
Most probably, best 20 years old diamonds would receive GIA triple EX today easily .

for example 20 years old 8star diamonds have very high optical symmetry and polishing. GIA rejected its only because of high crown painting .
We did not see many high symmetry diamonds 20 years ago because the production of such diamonds was too expensive . New technologies significantly increase productivity . it is possible to cut diamonds with high level symmetry now in 3-10 times faster than 20 years ago.
Because trade had not and still has not skill to sell better diamonds with reasonable premium then manufactures did not produce many high symmetry diamonds early.
 

Rockdiamond

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Thanks Serg.
I was lucky to be working for a massive company in the '80's- and saw literally millions of carats over time.
Most goods back then were definitely nowhere near as nice as the average stone today.
But the "Russian Make" of the '80's was spectacular and incredibly consistent.
There were also some US houses that were producing consistently excellent makes from the time I started, in 1976. But the fine makes of the day were indeed rare, costly- and hard to find.
 

Serg

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Thanks Serg.
I was lucky to be working for a massive company in the '80's- and saw literally millions of carats over time.
Most goods back then were definitely nowhere near as nice as the average stone today.
But the "Russian Make" of the '80's was spectacular and incredibly consistent.
There were also some US houses that were producing consistently excellent makes from the time I started, in 1976. But the fine makes of the day were indeed rare, costly- and hard to find.
David ,
I sure that most diamonds "Russian Make" of the '80's are not modern GIA 3EX. its were very consistent in 30-40 years ago because Russian manufactures used quality control independent from polishers. Standards of Russian's government manufacture internal certification was very different from GIA grading standards( not worse or better , but different )
 

Rockdiamond

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HI Serg,
At the time, they were referred to as "Russian Makes", but my knowledge of exactly where and how they were cut is limited. That's why the "quotes"- I believe it was an exclusive channel- but yes from Russia- but I can't be sure.
This was at the end of the USSR- I can't say how much the government was involved- but I do remember the diamonds. They were the best makes of the day, aside from LK, and a few select boutique cutters in NYC
GIA was rarely even discussed back then.
 

HDer

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Slightly off topic but there's another interesting idea this thread has made me think about:

Is it actually disadvantageous to a diamond's resale value to have it laser inscribed with its report number?

Given that diamonds are regraded as a regular practice and given that there's grade deflation/discounting it would be really awkward to explain to a potential buyer why actually the inscription on the girdle doesn't match the number on the report.

Or does GIA allow you to keep the same report number when the diamond is regraded?
 

gm89uk

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GIA can update the report with the same report number.
 
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