What procedures to follow when reflectors cannot (any longer) help?

[Regular Guy]

So, whether you think they didn''t help too much to begin with...or you think that...consistent with the HCA (in the case of a round), they''re only good for an initial screening...what specific procedures remain for...either an initial selection (in the case of David, as an example) or after the initial cut has passed muster (in the case of Serg).

In other words, to David in particular, when engaging in initial filtering for stock, you don''t look at everything that might pass through, do you? Too much, right? You have your own formula, based either on proportions...or something? What''s the something? Just trust in your own supplier, who has figured out your preferences? If so, what screening does he or she, do you think, do on your behalf?

And, to Serg, since lighting at least can confound, after using reflectors to control for that, what other controls, if any, can you exercise to select further?

Regards,

 

[Rockdiamond]

HI Ira,
I assume I''m the David you were referring to.
Thank you for starting this conversation.

to David in particular, when engaging in initial filtering for stock, you don''t look at everything that might pass through, do you? Too much, right?

Great question!
To answer completely you''ll need to understand how the cutters are working.
In fact, there are many different methods of how cutters display goods.
One of the places we buy colorless stones uses a fairly common method.
The diamonds are all in parcel papers, the papers lined up in boxes in categories.
Say Cushions D-G 1.00 and larger.
The parcel papers are labeled with most of the GIA info.
Color, Clarity Pol/SYM, Cut Grade ( in the case of rounds),measurements fluorescence- but no angles.
In such cases, I would simply pull each paper that is close to what we might be looking for, and open it.
First impressions are VERY important here.
Elimination at this stage is pretty straightforward.
IMPORTANT NOTE- using this method can mean we miss some amazing possibilities that were not in the Color clarity we had in mind. Simply shuffling through the papers is a good way to pick categories, but not to really "look at the goods" in total. Fancy Colors are a whole different ballgame- more on that later.

After we''ve "pre-selected" we get to take the goods back to our office and look at them in a more thorough manner. I like to look in the morning- then again in the evening.
I like to look in bright lights- and I like to put the diamond under the desk.

I''m going to make one of my "bold statements".
Maybe I should think longer about this but here''s my gut feeling.
If we take price out of the equation, I''ve found that there are no substantive problems a diamond might possess that are NOT visible with the standard equipment: a diamond and UV light, a ten power loupe, and tweezers.
If I am missing something, I welcome discussion in it.

So, if the price is right, and I like the way it looks ( after taking a few different looks), it''s a go.

You made a reference to lighting...and maybe equalizing lighting- a very good topic.
In that regard- do you feel most of us are pretty familiar with how lighting affects our eyes?

I do.


Of course how we buy, and how a consumer buys are related, but there are a completely different set of circumstances.
I''m time limited now, but I greatly appreciate the idea of discussing this in a friendly informative manner. I''m going to put some thought into this and answer again later.
Thanks again Ira.

 

[Regular Guy]

Hi, Davdi, yes, you''re the one I was asking for, thanks.

So...and maybe this is standard practice for how you and your colleagues work...and so where you say...

Date: 7/29/2009 3:36:28 PM
Author: Rockdiamond

In fact, there are many different methods of how cutters display goods.
One of the places we buy colorless stones uses a fairly common method.
The diamonds are all in parcel papers, the papers lined up in boxes in categories.
Say Cushions D-G 1.00 and larger.
The parcel papers are labeled with most of the GIA info.
Color, Clarity Pol/SYM, Cut Grade ( in the case of rounds),measurements fluorescence- but no angles.
In such cases, I would simply pull each paper that is close to what we might be looking for, and open it.
First impressions are VERY important here.
Elimination at this stage is pretty straightforward.
IMPORTANT NOTE- using this method can mean we miss some amazing possibilities that were not in the Color clarity we had in mind.....

....so, despite the shortcomings of this method, where you filter by desired color & clarity, eliminating those you weren''t looking for...there is otherwise NO other front end filter. You look at each one.

Maybe, in this case, if there is a substantive question, it is just...how would you select cutters to go to?

Since you are talking about colored options here, presumably some will more specialize here, and those are the ones you go to.

Primarily, as you describe this process, your eye seems to be the first and last filter. I wonder how common this is, and how unique your program is, based on your specialization.

Thanks,

 

[Rockdiamond]

Hi Ira,
This is a GREAT conversation!

How to choose a cutter.
That''s kind of like, "How to choose a mate"

If one wanted to go into the diamond business, by actually possessing diamonds ( as opposed to a DB list), you''d have to have cutter(s) behind you.

That''s one of the most difficult aspects to overcome, for a newcomer into the business.
Once you''re known to some larger cutters, others will start to actually come after you, as a buyer.

But say you''ve overcome that obstacle. Then what?

Primarily, as you describe this process, your eye seems to be the first and last filter. I wonder how common this is, and how unique your program is, based on your specialization.

Also an amazing question.
It''s incredibly common in both colorless as well as fancy colors.
In fact, I''ve not seen other buyers in cutter''s offices using any other method beside using their eyes and the GIA report to calculate overall prices but examining the diamond itself as the deciding factor.

BTW- we''re talking about larger stones, with GIA reports.
Picking stones out of parcels- stones that have no GIA reports is another aspect.
Say stones for a tennis bracelet.
By and large, that''s done by eye, and using a MM gauge.


So, in a practical sense, the methods used by many PS readers ( ASET/IS and calculating based on angles and percentages) is virtually never used at the higher levels in the diamond business as a whole- of course some of the PS vendors are notable exceptions.

Putting this in perspective, that makes the work Garry does quite remarkable.
Most all the wholesale buyers use the eye as the final method- which, if my "bold" statement before is correct, and you can actually look at the diamonds, why would a buyer consider an ASET?
Furthermore, if you were looking at the diamond, and found no problems- or actually were drawn to the diamond based on it''s visual aspects, why involve additional tools?

So, in a sense, Garry put a tremendous amount of effort and research into something that was not specifically being asked for at the wholesale level. Making him a trailblazer. I can really respect that.

My feelings about the use of IS have not changed at all- I don''t use it- but my feelings about the motivation and effort put into these tolls has changed - a lot.

I''ll admit that I find over-complication to be a problem. And I can use visual methods to pick.
For a consumer who has decided to take things into their own hands and decide outside a dealer''s advice- or even to re-enforce a dealer''s advice, it seems to make a lot of sense to use ASET/IS

To use it at the wholesale level, when you are buying diamonds based on traditional, well proven methods, it seems totally extraneous.

I think part of the conflict stems from this.
If ASET/IS are used, it takes the judgment away from the dealer.

I honestly believe that the actual visual aspects are most important, and that taking the decision making out of the eyes of a person, and into the ASET/IS will mean a lot of great stones get lost along the way.
If the cutter did an amazing job, and I went over there and didn''t look at the stone- but rather used a Sarin to do an ASET/IS and eliminated some amazing stones due to that, the cutter would not be pleased.
I''m not talking about eliminating bad stones- rather eliminating great stones that don''t do well on ASET/IS- they really DO exist out there.
If you don''t respect the cutters- who are the ones actually fueling the entire business, you won''t have a business very long.

SO- we can show value for both methods.

 

[Rockdiamond]

More thought about this....
My first answers were more based on my typical shopping- which is never for round diamonds.
Many dealers would use Sarin reports in their buying.
Especially true if they are buying for "ideal" purposes- such as the best PS vendors do.
I was thinking of the NY Diamond Dealers Club ( The DDC) where a Sarin cost $2 and many buyers go for them.

If a dealer was buying a round, or series of round diamonds, it might make better sense to look over the sarin reports first- and eliminate that way.
If it's a cushion, you really need to look at each and every one..oh the toil...heheh


Of course Fancy Colors also need to be looked at, one by one.

 

[litebrite]

Very interesting thread. As a consumer (sorry, can''t begin to think of myself as a prosumer yet), I''d love to hear from other vendors as well.

 

[Rockdiamond]

Date: 7/29/2009 8:54:58 PM
Author: litebrite
Very interesting thread. As a consumer (sorry, can't begin to think of myself as a prosumer yet), I'd love to hear from other vendors as well.

Huge ditto!
It's a huge diamond business- and we all travel in limited circles, to some extent.

I trade primarily in New York, I've never bought in Mumbai India, or Johannesburg South Africa. or so many of the of the places where wholesale diamond markets exist.

Quite possible different habits elsewhere!

Also a good possibility some of the dealers who have spent more time using tools like ASET/IS will certainly find great utility in them.

 

[lisa1.01fvs1]

I like this thread as it has bearing on my situation a bit.

David, how would you go about asessing a patented cut fancy like Tiffany''s Novo (modified brilliant cushion)?

Garry in an earlier thread mentioned using an ASET scope to chose the best stone in specific reference to the Novo.

To quote you, "For a consumer who has decided to take things into their own hands and decide outside a dealer''s advice- or even to re-enforce a dealer''s advice, it seems to make a lot of sense to use ASET/IS."

Are reflectors valid for this type of stone and if so what would I be looking for? Or what should I avoid (too much green for example). (I think I''ll start my own thread on this and get more specific input.)

My instinct is telling me to go with my eyes on this one in different lighting environments if possible.

This is why Sergey''s and others'' research into the capabilities and limitations of reflectors are so intriguing to me at the moment.

 

[Serg]

Hi Ira,
To find new fancy cut for MSS , shortly I use below method:
1) 3D model level
A) check LR and ETAS. If both below 0.8 I usualy reject diamond, but if this diamond has highest recomendation from person who sent me it I continue process
B) IS, ASET, Black zone metrics. I check distribution of black zones. If diamond has clear and big black zones , I do movies to check is it static black zones?
C) comparision movies with RBC AGS&H&A in two light iluminations
D) DETAS comparision
E) ray tracing study. Check cross ray ability
If diamond pass all these tests I buy it or order cutting.
2)After we recieve real diamond,check again 3D model then:
A) comparision movies in two light illuminations with RBC(MSS13)
B) visual comparision tests( several persons, several samples, several light types)

 

[ChunkyCushionLover]

Date: 7/30/2009 12:15:34 AM
Author: lisa1.01fvs1
I like this thread as it has bearing on my situation a bit.

David, how would you go about asessing a patented cut fancy like Tiffany's Novo (modified brilliant cushion)?

Garry in an earlier thread mentioned using an ASET scope to chose the best stone in specific reference to the Novo.

To quote you, 'For a consumer who has decided to take things into their own hands and decide outside a dealer's advice- or even to re-enforce a dealer's advice, it seems to make a lot of sense to use ASET/IS.'

Are reflectors valid for this type of stone and if so what would I be looking for? Or what should I avoid (too much green for example). (I think I'll start my own thread on this and get more specific input.)

My instinct is telling me to go with my eyes on this one in different lighting environments if possible.

This is why Sergey's and others' research into the capabilities and limitations of reflectors are so intriguing to me at the moment.

The novo is close to a a square cushion hearts and arrows.
Stones like this one and others like it are cut to very exact standards and you won't see too many like them http://www.goodoldgold.com/diamond/2106/ on this page you can see the IS., ASET and hearts viewer

If you are going into Tiffany's to buy already set stones the best way is to use your eyes in different lighting conditions. (In a darker room, in front of the window, under the desk etc.)
Alternatively you can buy a handheld AGS ASET for $25 and go in there with it I bet they will be shocked!

.

If you did look through an ASET get good back lighting and from the side and then you would be looking for the contrast of blue arrows and red almost everywherelse. The more green or background colour you saw the more light leakage.
It takes some getting used to, you have to line up the girdle of the diamond paralell to the lense and in focus.
The ASET is a lot more useful when you can't see the stone in person and can't really judge from a photograph or qualitative comments from the dealer what it might look like.

I would expect though if Tiffany's has quality control like Birks "Amorique" (sold at Mayors in the US) another patented cushion hearts and arrows that they all are cut to near the same specs and should have similar light performance.

 

[diagem]

Date: 7/30/2009 2:36:30 AM
Author: ChunkyCushionLover

Date: 7/30/2009 12:15:34 AM
Author: lisa1.01fvs1
I like this thread as it has bearing on my situation a bit.

David, how would you go about asessing a patented cut fancy like Tiffany''s Novo (modified brilliant cushion)?

Garry in an earlier thread mentioned using an ASET scope to chose the best stone in specific reference to the Novo.

To quote you, ''For a consumer who has decided to take things into their own hands and decide outside a dealer''s advice- or even to re-enforce a dealer''s advice, it seems to make a lot of sense to use ASET/IS.''

Are reflectors valid for this type of stone and if so what would I be looking for? Or what should I avoid (too much green for example). (I think I''ll start my own thread on this and get more specific input.)

My instinct is telling me to go with my eyes on this one in different lighting environments if possible.

This is why Sergey''s and others'' research into the capabilities and limitations of reflectors are so intriguing to me at the moment.

The novo is close to a a square cushion hearts and arrows.
Stones like this one and others like it are cut to very exact standards and you won''t see too many like them http://www.goodoldgold.com/diamond/2106/ on this page you can see the IS. ASET and hearts viewer

If you are going into Tiffany''s to buy already set stones the best way is to use your eyes in different lighting conditions. (In a darker room, in front of the window, under the desk etc.)
Alternatively you can buy a handheld AGS ASET for $25 and go in there with it I bet they will be shocked!

.

If you did look through an ASET get good back lighting and from the side and then you would be looking for the contrast of blue arrows and red almost everywherelse. The more green or background colour you saw the more light leakage.
It takes some getting used to, you have to line up the girdle of the diamond paralell to the lense and in focus.

Are you sure the "NOVO" is a patented cut.
I believe there is prior art...

 

[Lorelei]

Lisa, this page explains ASET,

http://www.highperformancediamonds.com/index.php?page=education-performance

In particular

RED is Direct Light (drawn from 45-75 degrees). Red will be the most intense. It comes directly from the source.

GREEN is Reflected Light (drawn from 0-45 degrees). Green has less intensity. It is light reflected from walls, the environment, etc.

BLUE represents light Obscured by the observer (your head blocks this light from reaching the diamond). These areas will light up when the diamond is tilted and other areas will become shaded.

WHITE (if the diamond is backlit, as above) or BLACK (if not) is Leakage. These areas show where pavilion facets are acting as windows rather than mirrors. You see white because those windows allow you to look through the diamond and see the light underneath. White should be minimized.

In general RED should be maximized. Some BLUE is necessary. Too much GREEN is undesirable. The distribution of the three colors is important. WHITE should be minimized.

Different Shapes have Different Standards

Each cut has its own set of light performance standards. Fancy cuts are not held to the same standards as Round Brilliants, which are the best at returning an abundance of RED direct light.

You can purchase an ASET below

http://www.ideal-scope.com/cart_zoom_item.asp?Id=23&ShowAdd=Y

And good to see you back also!

 

[Sharon101]

Date: 7/29/2009 9:20:24 PM
Author: Rockdiamond

Date: 7/29/2009 8:54:58 PM
Author: litebrite
Very interesting thread. As a consumer (sorry, can''t begin to think of myself as a prosumer yet), I''d love to hear from other vendors as well.

Huge ditto!
It''s a huge diamond business- and we all travel in limited circles, to some extent.

I trade primarily in New York, I''ve never bought in Mumbai India, or Johannesburg South Africa. or so many of the of the places where wholesale diamond markets exist.

Quite possible different habits elsewhere!

Also a good possibility some of the dealers who have spent more time using tools like ASET/IS will certainly find great utility in them.

Do you ever buy from Israel?

Fwiw, the method you describe is how my husband buys his stock. And price is part of the equation because sometimes he comes across sensational stones (not nec. diamonds) but the price makes it difficult to move, or there is no demand for it.

20 years ago my husbands main specialty just walked off the shelves. Sometimes before 9.00 in the morning they had done as many sales as today they do in a month! They were good times! Today they have had to change their specialty to keep afloat!!!!

I happen to know how hard it is to buy stock that allows you to stay in business. You cant survive by accident, you really have to know what you are doing. Agree?

 

[Serg]

Date: 7/30/2009 4:05:35 AM
Author: Lorelei
Lisa, this page explains ASET,

http://www.highperformancediamonds.com/index.php?page=education-performance

In particular

RED is Direct Light (drawn from 45-75 degrees). Red will be the most intense. It comes directly from the source.

GREEN is Reflected Light (drawn from 0-45 degrees). Green has less intensity. It is light reflected from walls, the environment, etc.

BLUE represents light Obscured by the observer (your head blocks this light from reaching the diamond). These areas will light up when the diamond is tilted and other areas will become shaded.

WHITE (if the diamond is backlit, as above) or BLACK (if not) is Leakage. These areas show where pavilion facets are acting as windows rather than mirrors. You see white because those windows allow you to look through the diamond and see the light underneath. White should be minimized.

In general RED should be maximized. Some BLUE is necessary. Too much GREEN is undesirable. The distribution of the three colors is important. WHITE should be minimized.

Different Shapes have Different Standards

Each cut has its own set of light performance standards. Fancy cuts are not held to the same standards as Round Brilliants, which are the best at returning an abundance of RED direct light.

You can purchase an ASET below

http://www.ideal-scope.com/cart_zoom_item.asp?Id=23&ShowAdd=Y

And good to see you back also!

Re: "

GREEN is Reflected Light (drawn from 0-45 degrees). Green has less intensity. It is light reflected from walls, the environment, etc.

"
And from Windows what are most brightness light sourses in most offices in daylight time

 

[Serg]

ASET image for good fancy cut should have good mix of red and green( may be more red than green, but what is more important green should be between red, green should seperate red zones). if you see read zones in part image and green zone in other part, it is not best cut. For example if table is red and crown facets are green or via versa, it is bad cut. If knot is red and shoulders are red, it is bad cut. You try find cuts with good mix green and red. Better if cut has more red than green, but if cut has not green , it can not be best cut

 

[Sharon101]

Date: 7/30/2009 5:16:52 AM
Author: Serg
ASET image for good fancy cut should have good mix of red and green( may be more red than green, but what is more important green should be between red, green should seperate red zones). if you see read zones in part image and green zone in other part, it is not best cut. For example if table is red and crown facets are green or via versa, it is bad cut. If knot is red and shoulders are red, it is bad cut. You try find cuts with good mix green and red. Better if cut has more red than green, but if cut has not green , it can not be best cut

Thank you for this explaination. It is really interesting. You have explained it in a really easy to understand way!

 

[oldminer]

I find it an interesting tidbit about how to interpret ASET images with more precision. However, most folks have the diamond and the ASET at the same time and their eyes can tell the stone is working well or not. The ASET is generally used to confirm reasonably visible attributes. The interpretation of ASET images sounds easy enough, but it is well beyond the consumer level to comfortably select a diamond from ASET images over the Internet. Wehn used as a screening tool, these explanations will help people as they are excellent for getting this rather complex interpretation processw into proper perspective.

 

[Garry H (Cut Nut)]

A simple experiment of Sergey''s that everyone can do is to place a spoon where you might look at a diamond in a room during the day and look at the reflections in the spoon.
You will see the light from celings, say warmish halogens and cooler flouro''s as well as very cold white bright window light. The cloudier and duller the day''s often make the brightest window light.
The spoon shows an office flouro and a window away from the sun.
don''t just read it - do it and look at your diamonds and see where the sparkles are coming from

 

[Garry H (Cut Nut)]

Sergey has also mentioned the french square - baguettes and squares (and emerald cuts with small corners) can return a lot of light when tested with ideal-scope, ASET, BS, and all the standard tools - but because they are only capable of redirecting light from 4 narrow directions back to your eye it is possible that entire zones of the diamond will remain dark thru a range of rocking motions.

 

[Garry H (Cut Nut)]

Here you can see that unless there is a light dead ahead or your body is blocking lights from any illumination zones - the stone will not have the capacity to return any light from an entire suit of facets.
(this is what Sergey was referring to when he mentioned persistant DiamCalc dark zones in movies.)

We will be using video''s in tightly controlled lighting environements as an important part of our cut development work.

But this is not to say that IS, ASET and many other tools are not part of the methods employed.

 

[Lorelei]

VERY cool Sergey and Garry - like the scarf example too!

 

[Garry H (Cut Nut)]

So here is a quiz - which is the best pear shape - and what other tools could we use for
1. selection
2. rejection

Are you confident that your decision is the right one if
a. you are advising somone else as a prosumer
or
b. making an unseen selection for yourself?

 

[stone-cold11]

One question about the ASET, is there a difference between a black background ASET and a white background ASET? Similar usage? If same, why would one want to use one over the other or why present both in the image?

Thanks.

 

[Ellen]

Date: 7/30/2009 8:28:20 AM
Author: Lorelei
VERY cool Sergey and Garry - like the scarf example too!

Ok, I feel like I'm playing "Where's Waldo". lol I have read, and reread, I cannot find the scarf!

I can find a spoon though....

Very interesting Serg and Gary!

Gary, I will guess the top pear is the better?

 

[Lorelei]

Date: 7/30/2009 8:57:50 AM
Author: Ellen

Date: 7/30/2009 8:28:20 AM
Author: Lorelei
VERY cool Sergey and Garry - like the scarf example too!

Ok, I feel like I'm playing 'Where's Waldo'. lol I have read, and reread, I cannot find the scarf!

I can find a spoon though....



Very interesting Serg and Gary!

Gary, I will guess the top pear is the better?

carre = scarf!

Well I assume it is a carre as in scarf they are using as an example!

Spoons are good = pudding.

 

[Ellen]

Date: 7/30/2009 9:06:30 AM
Author: Lorelei

carre = scarf!

Well I assume it is a carre as in scarf they are using as an example!

Spoons are good = pudding.

Ah, I see? lol

 

[Garry H (Cut Nut)]

There is a body of thought that says leakage is less important than light return.
personally I like to look for obstruction and leakage and when they are near eacxh other I reject the stone.

Sergey also mentioned that we have 2 eyes (stereo vision) the leakage from one view can be light return from another - this is imporant.

And another feature that is hard to describe - but i will try in the next few days - is that sometimes a stone can have an entire dark zoe thru a range of movements because of obstruction.

To help understand some of this have a look at the ASET images on the reference page http://www.ideal-scope.com/1.using_ASET_scope.asp where you will see I use movies to show how I use the ASET scope.
I did this a few years ago and it is remarkable how few prosumers (if any) have noticed it. This is how I buy fancy cuts with ASET.

 

[Serg]

Date: 7/30/2009 8:41:26 AM
Author: Stone-cold11
One question about the ASET, is there a difference between a black background ASET and a white background ASET? Similar usage? If same, why would one want to use one over the other or why present both in the image?

Thanks.

Black ASET does not show Leakage.
White ASET has too much colors for my Taste( too complex image)
Distribution is more clear in Black ASET,

 

[Sharon101]

Garry, are you going to tell us the answer about which is the best pear?

 

[stone-cold11]

Date: 7/30/2009 10:04:39 AM
Author: Serg

Date: 7/30/2009 8:41:26 AM

Author: Stone-cold11

One question about the ASET, is there a difference between a black background ASET and a white background ASET? Similar usage? If same, why would one want to use one over the other or why present both in the image?

Thanks.

Black ASET does not show Leakage.

White ASET has too much colors for my Taste( too complex image)

Distribution is more clear in Black ASET,

So what does the black in the Black ASET represents? Thanks.