60/60 diamond & HCA 1.6 - Why?

[Sokeai]

Dear fellow pricescopers,

Probably a much debated topic but can't seems to find similar posts via the search function. Did read up articles on 60/60 diamond from Pricescope and Nice Ice etc, apparently it does not sound good.

Kind of puzzled why 60% table 60.7% depth is able to achieve HCA 1.6, though it is commonly known as a rejection tool?

Light Return Very Good
Fire Excellent
Scintillation Very Good
Spread Excellent

Total Visual Performance 1.6 - Excellent within TIC range

 

[yssie]

absolutely nothing wrong with a well-proportioned 60/60 (and yes, they can and certainly do exist). There can also be badly-proportioned 60/60s, which is why so many articles tell you to beware sellers that use table and depth as the only indicators of 'make' or cut quality.

It is a different look - pros include likely greater spread b/c they're usually slightly shallower than "traditional H&A proportions", and so they also show less body colour, they often excel at white light return.
Some people prefer a stone that's more fiery in some environments, smaller table, etc..

 

[Garry H (Cut Nut)]

Some older members of the diamond industry share a strange fallacy that if a diamond has proportions of 60% depth and 60% table, then it will be beautiful. It’s a great idea, but it does not always work.

Two extreme examples of bad proportion combinations, both still 60:60, both ugly, have pavilion angles as low as 36 degrees and all the way up to and beyond 45 degrees. This range actually exists in older stones. Of all of the diamonds within this range of pavilion angles, only those between 40.2 and 41.2 degrees are likely to be worthy of consideration.
Girdle thickness is another variable – a very thin girdled stone can end up with too steep / deep in crown and pavilion angles and the opposite can be true if the girdle is too thick.

GIA is the largest most prolific lab and there are 40 crown and pavilion angle combinations that receive its top cut grade of Excellent (although Pricescope addicts would only recommend about 20 of these). AGS list 26 angle combinations that potentially should achieve AGS 0 or Ideal (compared with 32 for a 56% table size).

 

[Dreamer_D]

absolutely nothing wrong with a well-proportioned 60/60 (and yes, they can and certainly do exist). There can also be badly-proportioned 60/60s, which is why so many articles tell you to beware sellers that use table and depth as the only indicators of 'make' or cut quality.

It is a different look - pros include likely greater spread b/c they're usually slightly shallower than "traditional H&A proportions", and so they also show less body colour, they often excel at white light return.
Some people prefer a stone that's more fiery in some environments, smaller table, etc..

Yuppers to this.

It does result in a slightly different look to the facet patterning than a traditional H&A, but to all but the most discering eye a well proportioned 60/60 would probably look great and the subtle nuances would not be obvious.

 

[Amys Bling]

Here is more information on the 60/60 diamond and why some will score under 2.0 on the HCA and be beautiful stones!

https://www.pricescope.com/wiki/diamonds/60-60-proportioned-diamond/

 

[Garry H (Cut Nut)]

Here is more information on the 60/60 diamond and why some will score under 2.0 on the HCA and be beautiful stones!

https://www.pricescope.com/wiki/diamonds/60-60-proportioned-diamond/

Hi Amy's - my post above is partially a re-write of that page - which somewhow was missed because it is very old (embarrassingly) which was prompted by this thread

 

[BAM54321]

Garry- Well said. Simple, yet very insightful. Thanks for taking the time.

 

[Rockdiamond]

I agree with Garry's point that the page linked to is woefully outdated- and sorely needs a re-write.

I don't agree with the suggestion that simply because someone is experienced ( and possibly older) they are simplistic enough to look only at a stone's table and depth to ascertain how well it's cut.
Along with the lgf, the larger table of a well proportioned 60/60 produces a look that's different from the current crop of "Ideal" cut stones- and will be preferable to many of the most discerning eyes - be they trade members or not. Seasoned trade members , if they are "mavens' will look at stones holistically.
In fact, I see a totally different phenomenon.
That being- mediocre cut stones that are cut with smaller tables and shorter lgf's to emulate the H&A pattern in an attempt to pass them off as really well cut stones.
We all agree that one needs to consider proportions, lgf as well as a diamond's physical characteristics to ascertain it's cut quality.

 

[Amys Bling]

Here is more information on the 60/60 diamond and why some will score under 2.0 on the HCA and be beautiful stones!

https://www.pricescope.com/wiki/diamonds/60-60-proportioned-diamond/

Hi Amy's - my post above is partially a re-write of that page - which somewhow was missed because it is very old (embarrassingly) which was prompted by this thread

Sorry for digging up the old thread...lol. For once I was trying to take initiative to reference a resource instead of just stating an opinion.

 

[Rockdiamond]

Hi Amy- from where I sit, I would like to thank you for sharing the link!
It's an interesting subject, and the link really does put some perspective into this discussion( and might light a fire under Garry's butt to do an edit )

 

[Garry H (Cut Nut)]

Hi Amy- from where I sit, I would like to thank you for sharing the link!
It's an interesting subject, and the link really does put some perspective into this discussion( and might light a fire under Garry's butt to do an edit )

I already wrote that my earlier post was an edit of it RD.
I sent it to Andrey and Erika BEFORE my first post in this thread.
Down under we your comments "flogging a dead horse".

 

[Garry H (Cut Nut)]

Here is more information on the 60/60 diamond and why some will score under 2.0 on the HCA and be beautiful stones!

https://www.pricescope.com/wiki/diamonds/60-60-proportioned-diamond/

Hi Amy's - my post above is partially a re-write of that page - which somewhow was missed because it is very old (embarrassingly) which was prompted by this thread

Sorry for digging up the old thread...lol. For once I was trying to take initiative to reference a resource instead of just stating an opinion.

You did great Amy

 

[Rockdiamond]

Once again our different versions of English seem remarkable G!

I'll be anxiously awaiting the publishing of the rewrite! ( so we can save the poor dead horse)

 

[Dancing Fire]

just stay away from em 60/60 "flat top" stones ...

 

[yssie]

just stay away from em 60/60 "flat top" stones ...

now there's an objective observation for 'ya ..

 

[Garry H (Cut Nut)]

Here is more information on the 60/60 diamond and why some will score under 2.0 on the HCA and be beautiful stones!

https://www.pricescope.com/wiki/diamonds/60-60-proportioned-diamond/

Amy that page has been updated.
There is a minor change / edit to be made, but of no consequence.

 

[Rockdiamond]

Garry, all due respect, but is it really necessary to degrade people in the business due to their age?

I happen to know some extremely sharp folks who've been in this business for longer than I've been alive. That includes being able to look at stones- be they 60/60, or 57/62 and have a very good feel for the quality of cut. Without using aset/IS or any tools other than a loupe.
I'm actually sure you can do that as well- and you're probably in my age range ( I'm 53)

Also - the two top images are a parody.
Do you know any diamond man ( or woman)- no matter how old- that would call any stone looking like that well cut?

"PS addicts"- is also a generalization- a broad one. I have no doubt that there are a fair number of people who love this site , and would find stones other than your chosen 20 combos to be very attractive- I'd even go as far to say that some "PS addicts" will find some of the CA/PA combos that you exclude to be nicer than others that you include.
If you're going to fix the page, why not really do it right, and without pejorative remarks.

Just my .02

 

[Garry H (Cut Nut)]

Garry, all due respect, but is it really necessary to degrade people in the business due to their age?

I happen to know some extremely sharp folks who've been in this business for longer than I've been alive. That includes being able to look at stones- be they 60/60, or 57/62 and have a very good feel for the quality of cut. Without using aset/IS or any tools other than a loupe.
I'm actually sure you can do that as well- and you're probably in my age range ( I'm 53)

Also - the two top images are a parody.
Do you know any diamond man ( or woman)- no matter how old- that would call any stone looking like that well cut?

"PS addicts"- is also a generalization- a broad one. I have no doubt that there are a fair number of people who love this site , and would find stones other than your chosen 20 combos to be very attractive- I'd even go as far to say that some "PS addicts" will find some of the CA/PA combos that you exclude to be nicer than others that you include.
If you're going to fix the page, why not really do it right, and without pejorative remarks.

Just my .02

I guess the main difference of opinion here is that the site is to assist consumers to make their own selection David, and not 'NEED' to trust any vendor, irrespective of age or experiance.
You and I have both seen plenty of old cut dimaonds with the parameters in that image.
Today, thank heavens, there are very few diamonds cut to these paprameters. However the point is that 60:60 means nothing, and when oldtimers had nothing to go by other than table, depth and polish and symmetry, and they were flipping stones unseen based on certs - many people ended up with dogs and cutters were rewarded for cheating.

Now what part of what I wrote is not valid?

 

[Dancing Fire]

Here is more information on the 60/60 diamond and why some will score under 2.0 on the HCA and be beautiful stones!

https://www.pricescope.com/wiki/diamonds/60-60-proportioned-diamond/

Amy that page has been updated.
There is a minor change / edit to be made, but of no consequence.

had one that looks like the one on the bottom .. an ugly "flat top" 60/60 stone with no fire ...

 

[Lula]

Here is more information on the 60/60 diamond and why some will score under 2.0 on the HCA and be beautiful stones!

https://www.pricescope.com/wiki/diamonds/60-60-proportioned-diamond/

Amy that page has been updated.
There is a minor change / edit to be made, but of no consequence.

had one that looks like the one on the bottom .. an ugly "flat top" 60/60 stone with no fire ...

I've seen those, too, and they are not pretty, but they are still quite common. I also agree with David (RockDiamond) that there are some poorly cut H&A diamonds. There appear to be many ways for cutters to "cheat" the system, so buying an "H&A" is no guarantee that you'll get a well-cut diamond.

60/60 cuts and H&A cuts look different. You may prefer one style over the other. This article https://www.pricescope.com/journal/laboratory_cut_grades_what_report_doesn’t_show shows examples of well-cut and poorly-cut diamonds in both cutting styles.

ETA: I can't get my link to work -- can somebody please fix it?

 

[stone-cold11]

Cannot get the url to work too. I have reported it to the admin.

 

[Rockdiamond]

Garry, all due respect, but is it really necessary to degrade people in the business due to their age?

I happen to know some extremely sharp folks who've been in this business for longer than I've been alive. That includes being able to look at stones- be they 60/60, or 57/62 and have a very good feel for the quality of cut. Without using aset/IS or any tools other than a loupe.
I'm actually sure you can do that as well- and you're probably in my age range ( I'm 53)

Also - the two top images are a parody.
Do you know any diamond man ( or woman)- no matter how old- that would call any stone looking like that well cut?

"PS addicts"- is also a generalization- a broad one. I have no doubt that there are a fair number of people who love this site , and would find stones other than your chosen 20 combos to be very attractive- I'd even go as far to say that some "PS addicts" will find some of the CA/PA combos that you exclude to be nicer than others that you include.
If you're going to fix the page, why not really do it right, and without pejorative remarks.

Just my .02

I guess the main difference of opinion here is that the site is to assist consumers to make their own selection David, and not 'NEED' to trust any vendor, irrespective of age or experiance.
You and I have both seen plenty of old cut dimaonds with the parameters in that image.
Today, thank heavens, there are very few diamonds cut to these paprameters. However the point is that 60:60 means nothing, and when oldtimers had nothing to go by other than table, depth and polish and symmetry, and they were flipping stones unseen based on certs - many people ended up with dogs and cutters were rewarded for cheating.

Now what part of what I wrote is not valid?

Let's start with this part- and I need to preface this by saying I am not looking to fight- but I think these are important aspects of how each of us looks at diamonds, and the diamond business.
Unless the consumer can go to the mine, pull the diamond out of the earth, polish it, then make their own ring, trust is going to be essential.
I'm not saying a blind "trust me" is the answer by any means- yet consumers are best served if they find a seller that is worthy of their trust.
At some point they need to hand over the dollars, and get a stone in return.
They need to know it's the same stone on the GIA report, for example.

We both agree that informed consumers are in a far better position.
My feeling is that helping them to select a seller is just as ( if not more) important than helping them to read an aset.

 

[Rockdiamond]

Point #2

Some older members of the diamond industry share a strange fallacy that if a diamond has proportions of 60% depth and 60% table, then it will be beautiful. It’s a great idea, but it does not always work.

Garry- again, I'm not looking to argue, but this statement is akin to judging someone based on the color of their skin, sexual orientation, or a whole host of other attributes that are rightfully seen as racist, sexist, etc.
I'd suggest that in addition to some older folks, there's a lot of younger sellers of diamonds are pawning "off make" goods with substandard reports in an attempt to deceive consumers.

I do agree that there are badly cut diamonds out there, and we want to assist consumers in avoiding badly cut stones.
The point is that a person's age is not relevant in a discussion of judging diamonds.

 

[Garry H (Cut Nut)]

Point #2

Some older members of the diamond industry share a strange fallacy that if a diamond has proportions of 60% depth and 60% table, then it will be beautiful. It’s a great idea, but it does not always work.

Garry- again, I'm not looking to argue, but this statement is akin to judging someone based on the color of their skin, sexual orientation, or a whole host of other attributes that are rightfully seen as racist, sexist, etc.
I'd suggest that in addition to some older folks, there's a lot of younger sellers of diamonds are pawning "off make" goods with substandard reports in an attempt to deceive consumers.

I do agree that there are badly cut diamonds out there, and we want to assist consumers in avoiding badly cut stones.
The point is that a person's age is not relevant in a discussion of judging diamonds.

Wink and I are older than you.
I have not heard of a lot of young retailers pushing 60:60.

 

[Rockdiamond]

No one is "pushing" 60/60 Garry.
Such stones are truly rare birds in today's market.
Much of what we see today in off make stones is "pseudo H&A" as opposed to 60/60 look-alikes.

The attributes of well cut 60/60 stones with longer lgf's seems lost in today's market- those attributes being very good spread, and a more even sparkle as compared to near tolks. "Ideal" cut may have more fire, but a well cut 60/60 with longer lgf's has more brilliance and scintillation IMO

Even years ago, off make stones that I saw looked nothing like the two profile examples at the top of your 60/60 page.
I'd like to the the diacalc of those two unlikely examples head on, as opposed to profile, if that's possible.

 

[Garry H (Cut Nut)]

No one is "pushing" 60/60 Garry.
Such stones are truly rare birds in today's market.
Much of what we see today in off make stones is "pseudo H&A" as opposed to 60/60 look-alikes.

The attributes of well cut 60/60 stones with longer lgf's seems lost in today's market- those attributes being very good spread, and a more even sparkle as compared to near tolks. "Ideal" cut may have more fire, but a well cut 60/60 with longer lgf's has more brilliance and scintillation IMO

Even years ago, off make stones that I saw looked nothing like the two profile examples at the top of your 60/60 page.
I'd like to the the diacalc of those two unlikely examples head on, as opposed to profile, if that's possible.

I think you push them, are you no-one?

 

[Rockdiamond]

Thanks for the diacalcs Garry- we'd have to look pretty far and wide to find anyone who would look at such a diamond and feel it's worth buying, agreed?

I think you push them, are you no-one?

I would like to think I'm someone Garry.
But I think you have the wrong impression.
First of all, we don't even carry a lot of round colorless diamonds. I don't have a ready source of long lgf 60/60's to protect, or push, as it were.
What I "push" is an idea- that being a different way of judging the cut of diamonds.
I happen to respect you tremendously- and your work.
I think that sometimes it's taken out of context- which can be a problem in many ways.

What I mean is this: Say someone wants a near tolk- by all means, use the tools available- aset/is/ HCA

But what I have worked very to make clear is that not everyone loves a near tolk- and in fact, other stones that may look "worse" in an aset- or get downgraded by HCA may, in fact, be just as well cut- and actually preferable to a lot of people.

The op's question proves my point- clearly there's an impression ( around here) that 60/60 is a bad thing.

 

[Garry H (Cut Nut)]

But what I have worked very to make clear is that not everyone loves a near tolk- and in fact, other stones that may look "worse" in an aset- or get downgraded by HCA may, in fact, be just as well cut- and actually preferable to a lot of people.

Who, how many, show some evidence to support that. There are litterally thousands of people who disagree. Can you find more than 5% of diamond consumer buyers who support your position?

The op's question proves my point- clearly there's an impression ( around here) that 60/60 is a bad thing.
That has never ever been my position - play with HCA with 60% table sizes AND remember I developed it when AGS were saying any diamond with a table larger than 58% was inferior.

 

[Rockdiamond]

But what I have worked very to make clear is that not everyone loves a near tolk- and in fact, other stones that may look "worse" in an aset- or get downgraded by HCA may, in fact, be just as well cut- and actually preferable to a lot of people.

Who, how many, show some evidence to support that. There are litterally thousands of people who disagree. Can you find more than 5% of diamond consumer buyers who support your position?

Garry- I don't see how this question is answerable with "evidence" or statistics- by anyone. We can point to the GIA study as the most extensive, yet even that is easy to fault. I can only use my own experience- and eye for beauty. There have been many posts here on PS where people have stated a preference against H&A

The op's question proves my point- clearly there's an impression ( around here) that 60/60 is a bad thing.
That has never ever been my position - play with HCA with 60% table sizes AND remember I developed it when AGS were saying any diamond with a table larger than 58% was inferior.

There is a bit of history here Garry- back in the old days, before the 2006 GIA cut grade, I was on PS defending the larger table, more shallow proportions of a well cut 60/60. Is it possible that may have been part of the motivation for the 60/60 page?

I don't feel that you are consciously attempting to "defame" 60/60- yet the page is simply prejudicial.
As far as using the HCA to judge 60/60's- it has been my experience that in a number of cases there have been stones which I found to be quite remarkable- whose cut was not lacking in any way, yet they score below 4 or even below 5 on HCA.

 

[Lula]

*Sigh* ETA: Nevermind.