Diamond Buying by the Numbers - Perspective.

[ChunkyCushionLover]

Date: 4/23/2010 10:32:25 PM
Author: Karl_K

Date: 4/23/2010 3:05:17 PM
Author: ChunkyCushionLover

Anyone care to comment on the appearance of these two images and what deviation from ideal you would see in a sarin that causes the broken offset arrows and the areas showing green in the ASET?

This is a ''Near HA'' round.

Cant comment on the diamond itself.
In general:

This type of variation if it shows up at all on a sarin scan will only show up on the 3d scan/viewer.
A full helium report would also give a clue.
The standard sarin report will not show it.
9 times out of 10 variation in the arrows is really variation in the lower girdles affecting the mains.
The other time it is a wide variation in angle and or placement of the mains.
This also explains why you could have .1 variation in the mains angle with broken arrows and wacky hearts.
Look at a wire diagram of a diamond and you will see why that makes sense.

Also read and understand this article:
http://journal.pricescope.com/Articles/68/1/Do-the-pavilion-mains-drive-light-return-in-the-modern-round-brilliant.aspx

You mean from the deviation in LGF or a couple of mismatched LGF to main you can get broken arrows and wacky hearts and this is independant from the pavillion main angles which may have little deviation from from one another.
So it could be the case, its not the variation or placement of the mains but likely some of the LGF angles that don''t fit the main angles.

In the linked article the focus is under the table, in these images there is no problem under the table but it is the areas in the top part of the LGF that are showing signs of only gathering light from the lower angles.

 

[Karl_K]

Date: 4/24/2010 9:52:32 AM
Author: ChunkyCushionLover

In the linked article the focus is under the table, in these images there is no problem under the table but it is the areas in the top part of the LGF that are showing signs of only gathering light from the lower angles.

uneven painting/digging is causing the green mainly on the uppers but looks like maybe the lowers also.
It wouldn''t surprise me that the broken arrows are the result of that also on the lgf.

 

[melz]

I believe the images CCL posted earlier were of a diamond I was looking at. Here is the hearts image if anyone is interested:

 

[LD]

Please don''t stone me to death for this post but I have a slightly different take on this .............

Unless I''m mistaken - and forgive me because I''ve only done some speed reading - not one post above has mentioned the most valuable tool available to the majority - their eyes! I''ve occasionally seen assets etc of diamonds and people have said that the numbers look good (based on only the information provided which may not have been enough) and then up comes a photo of a diamond and eeeeek! There was a classic example a while ago of a pear diamond. Apparently the stats were good (I''ve got no idea because I get lost with the technical aspects) but then the picture was posted and there was the biggest bowtie in the world! Now, irrespective of what the numbers say, wild horses wouldn''t have driven me to buy that diamond.

I honestly appreciate that stats, images etc are used (or SHOULD only be used) to screen out diamonds with potential issues but I have a horrible feeling that people buy on the numbers alone and some potentially very very very beautiful stones get lost in the mix.

I fully respect the opinion of those who give their time to advise on potential purchases and have asked questions myself (and learned much in the process) but I''m really concerned that people aren''t told enough to go see the diamond in action. Look at it in different lighting situations etc.

 

[Dancing Fire]

Date: 4/24/2010 7:17:44 PM
Author: LovingDiamonds
Please don''t stone me to death for this post but I have a slightly different take on this .............

Unless I''m mistaken - and forgive me because I''ve only done some speed reading - not one post above has mentioned the most valuable tool available to the majority - their eyes! I''ve occasionally seen assets etc of diamonds and people have said that the numbers look good (based on only the information provided which may not have been enough) and then up comes a photo of a diamond and eeeeek! There was a classic example a while ago of a pear diamond. Apparently the stats were good (I''ve got no idea because I get lost with the technical aspects) but then the picture was posted and there was the biggest bowtie in the world! Now, irrespective of what the numbers say, wild horses wouldn''t have driven me to buy that diamond.

I honestly appreciate that stats, images etc are used (or SHOULD only be used) to screen out diamonds with potential issues but I have a horrible feeling that people buy on the numbers alone and some potentially very very very beautiful stones get lost in the mix.

I fully respect the opinion of those who give their time to advise on potential purchases and have asked questions myself (and learned much in the process) but I''m really concerned that people aren''t told enough to go see the diamond in action. Look at it in different lighting situations etc.

the problem with that theory ....if i asked my daughter to pick out a stone that her eyes loves the most can still turn out to be a POS,b/c my daugther as a first time buyer haven''t seen a well cut stone in her life.remember,even a crappy stone will look like a monster stone to a first time buyer.

 

[LD]

Date: 4/24/2010 7:44:18 PM
Author: Dancing Fire

Date: 4/24/2010 7:17:44 PM
Author: LovingDiamonds
Please don't stone me to death for this post but I have a slightly different take on this .............

Unless I'm mistaken - and forgive me because I've only done some speed reading - not one post above has mentioned the most valuable tool available to the majority - their eyes! I've occasionally seen assets etc of diamonds and people have said that the numbers look good (based on only the information provided which may not have been enough) and then up comes a photo of a diamond and eeeeek! There was a classic example a while ago of a pear diamond. Apparently the stats were good (I've got no idea because I get lost with the technical aspects) but then the picture was posted and there was the biggest bowtie in the world! Now, irrespective of what the numbers say, wild horses wouldn't have driven me to buy that diamond.

I honestly appreciate that stats, images etc are used (or SHOULD only be used) to screen out diamonds with potential issues but I have a horrible feeling that people buy on the numbers alone and some potentially very very very beautiful stones get lost in the mix.

I fully respect the opinion of those who give their time to advise on potential purchases and have asked questions myself (and learned much in the process) but I'm really concerned that people aren't told enough to go see the diamond in action. Look at it in different lighting situations etc.

the problem with that theory ....if i asked my daughter to pick out a stone that her eyes loves the most can still turn out to be a POS,b/c my daugther as a first time buyer haven't seen a well cut stone in her life.remember,even a crappy stone will look like a monster stone to a first time buyer.

But ........... so what!!! If the person loves what they see, does it matter whether it's a monster or not? That's my whole point. Beauty should be in the eye of the beholder, not statistics. One of my most beautiful diamonds is an old mine cut. It wouldn't pass any numbers test but it's an absolutely stunning beauty (to me).

By the way, it's not a theory. This is how all coloured stones are bought.

 

[yssie]

Date: 4/24/2010 7:58:15 PM
Author: LovingDiamonds

Date: 4/24/2010 7:44:18 PM
Author: Dancing Fire

Date: 4/24/2010 7:17:44 PM
Author: LovingDiamonds
Please don't stone me to death for this post but I have a slightly different take on this .............

Unless I'm mistaken - and forgive me because I've only done some speed reading - not one post above has mentioned the most valuable tool available to the majority - their eyes! I've occasionally seen assets etc of diamonds and people have said that the numbers look good (based on only the information provided which may not have been enough) and then up comes a photo of a diamond and eeeeek! There was a classic example a while ago of a pear diamond. Apparently the stats were good (I've got no idea because I get lost with the technical aspects) but then the picture was posted and there was the biggest bowtie in the world! Now, irrespective of what the numbers say, wild horses wouldn't have driven me to buy that diamond.

I honestly appreciate that stats, images etc are used (or SHOULD only be used) to screen out diamonds with potential issues but I have a horrible feeling that people buy on the numbers alone and some potentially very very very beautiful stones get lost in the mix.

I fully respect the opinion of those who give their time to advise on potential purchases and have asked questions myself (and learned much in the process) but I'm really concerned that people aren't told enough to go see the diamond in action. Look at it in different lighting situations etc.

the problem with that theory ....if i asked my daughter to pick out a stone that her eyes loves the most can still turn out to be a POS,b/c my daugther as a first time buyer haven't seen a well cut stone in her life.remember,even a crappy stone will look like a monster stone to a first time buyer.

But ........... so what!!! If the person loves what they see, does it matter whether it's a monster or not? That's my whole point. Beauty should be in the eye of the beholder, not statistics. One of my most beautiful diamonds is an old mine cut. It wouldn't pass any numbers test but it's an absolutely stunning beauty (to me).

I think DF's point is that the monster will be beautiful in the eye of the beholder until that beholder sees a true ideal cut sparkler that outperforms hers in all sorts of lights. Then the regret sets in and the questions start coming... and the answers to those questions lie in the optics, which stem directly from the numbers.

Performance isn't like gem colour, I think. A colour that one person loves can legitimately be something that another hates.. but when two diamonds of the same shape and style are offered, one dull and the other sparkly and lively, I don't think anyone in the world would deliberately choose the dull one for something like an Ering (perhaps as a curio stone).

 

[Dancing Fire]

Date: 4/24/2010 7:58:15 PM
Author: LovingDiamonds

Date: 4/24/2010 7:44:18 PM
Author: Dancing Fire



the problem with that theory ....if i asked my daughter to pick out a stone that her eyes loves the most can still turn out to be a POS,b/c my daugther as a first time buyer haven''t seen a well cut stone in her life.remember,even a crappy stone will look like a monster stone to a first time buyer.

But ........... so what!!! If the person loves what they see, does it matter whether it''s a monster or not? That''s my whole point. Beauty should be in the eye of the beholder, not statistics. One of my most beautiful diamonds is an old mine cut. It wouldn''t pass any numbers test but it''s an absolutely stunning beauty (to me).

By the way, it''s not a theory. This is how all coloured stones are bought.

agree,but i wasn''t referring to OMC or colored stones.

 

[Dancing Fire]

Date: 4/24/2010 8:00:23 PM
Author: yssie

I think DF''s point is that the monster will be beautiful in the eye of the beholder until that beholder sees a true ideal cut sparkler that outperforms hers in all sorts of lights. Then the regret sets in and the questions start coming... and the answers to those questions lie in the optics, which stem directly from the numbers.

Performance isn''t like gem colour, I think. A colour that one person loves can legitimately be something that another hates.. but when two diamonds of the same shape and style are offered, one dull and the other sparkly and lively, I don''t think anyone in the world would deliberately choose the dull one for something like an Ering (perhaps as a curio stone).

yssie...
thanks,that''s what i was trying to say.

 

[ChunkyCushionLover]

Date: 4/24/2010 7:58:15 PM
Author: LovingDiamonds

Date: 4/24/2010 7:44:18 PM
Author: Dancing Fire

Date: 4/24/2010 7:17:44 PM
Author: LovingDiamonds
Please don't stone me to death for this post but I have a slightly different take on this .............

Unless I'm mistaken - and forgive me because I've only done some speed reading - not one post above has mentioned the most valuable tool available to the majority - their eyes! I've occasionally seen assets etc of diamonds and people have said that the numbers look good (based on only the information provided which may not have been enough) and then up comes a photo of a diamond and eeeeek! There was a classic example a while ago of a pear diamond. Apparently the stats were good (I've got no idea because I get lost with the technical aspects) but then the picture was posted and there was the biggest bowtie in the world! Now, irrespective of what the numbers say, wild horses wouldn't have driven me to buy that diamond.

I honestly appreciate that stats, images etc are used (or SHOULD only be used) to screen out diamonds with potential issues but I have a horrible feeling that people buy on the numbers alone and some potentially very very very beautiful stones get lost in the mix.

I fully respect the opinion of those who give their time to advise on potential purchases and have asked questions myself (and learned much in the process) but I'm really concerned that people aren't told enough to go see the diamond in action. Look at it in different lighting situations etc.

the problem with that theory ....if i asked my daughter to pick out a stone that her eyes loves the most can still turn out to be a POS,b/c my daugther as a first time buyer haven't seen a well cut stone in her life.remember,even a crappy stone will look like a monster stone to a first time buyer.

But ........... so what!!! If the person loves what they see, does it matter whether it's a monster or not? That's my whole point. Beauty should be in the eye of the beholder, not statistics. One of my most beautiful diamonds is an old mine cut. It wouldn't pass any numbers test but it's an absolutely stunning beauty (to me).

By the way, it's not a theory. This is how all coloured stones are bought.

LD this thread relates to rounds, for fancy shapes the prevailing opinion is usually not to judge too strictly by the numbers.

Even so I point you to the following :
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Simplifie Example:

Customer walks into a diamond shop of a vendor who doesn't use modern technology for diamond selection and only sells non branded or non ideal cut round brilliant diamonds:

Dealer shows them 10 diamonds they are all pretty no surprise, diamonds in jewelry store lights usually are.
Customer being diamond savvy views the diamonds in the window, under a table etc. and then finds now only 3 are pretty to them in different lighting.
Dealer says "trust my experience and what your eyes see" and suggests 1 of the three.
Customer purchases that diamond and is confident they chose the most beautiful diamond for them. After all it was the best one out of the 10 and the "expert" dealer said so.

A) Now customer walks down the street and looks at some branded ideal cut H&A diamonds with all the reflector tests, hearts and arrows images and full sarin data but they are priced 10 - 20% more and says wow my "most beautiful" diamond isn't as beautiful as these ones I wish I had paid the premium.

Or

B) Customer says well these are nice but not 20% better I'm happy with my choice.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
We go through an awful lot of trouble on this board to make sure a consumer can make an informed choice between scenario A or B, far more than any vendor selling one or the other would.

 

[LD]

I understand all of the above. However, there ARE consumers who don''t like the more perfect look of, say, a H&A diamond. Some that score highly don''t perform well in certain lighting situations and can black out. I would rather buy a beautiful diamond (irrespective of what the numbers say) without paying a premium. Perhaps I''m alone in that thought process but up until now I''ve never had to use numbers to buy anything and I don''t regret any of my purchases (or wish I had had more information at the start). What I found highly informative was when I was looking at asschers and Karl told me what to look for in terms of the cut itself (not numbers). That helped me to evaluate the diamonds I was looking at enormously. The numbers would have just blown my mind! This is only my perspective and I appreciate that I''m in the minority on this section of the forum but I still think it''s sad that people aren''t told to use their eyes more. Sorry!

 

[Garry H (Cut Nut)]

Date: 4/25/2010 6:25:45 AM
Author: LovingDiamonds
I understand all of the above. However, there ARE consumers who don''t like the more perfect look of, say, a H&A diamond. Some that score highly don''t perform well in certain lighting situations and can black out. I would rather buy a beautiful diamond (irrespective of what the numbers say) without paying a premium. Perhaps I''m alone in that thought process but up until now I''ve never had to use numbers to buy anything and I don''t regret any of my purchases (or wish I had had more information at the start). What I found highly informative was when I was looking at asschers and Karl told me what to look for in terms of the cut itself (not numbers). That helped me to evaluate the diamonds I was looking at enormously. The numbers would have just blown my mind! This is only my perspective and I appreciate that I''m in the minority on this section of the forum but I still think it''s sad that people aren''t told to use their eyes more. Sorry!

Do not be sorry LD

I do both - I try to correlate what I see with the numbers.
I can not remeber the last time I saw a diamond with ok colour, clarity and transparency - where my interpretation of numbers and what I saw were in conflict.

It is now so much this way that using all the tools that I use (eyes, Ideal-scope, ASET if the stone is fancy shape (waste of time for rounds) and various types of light) - I prefer to have a good 3D model and DiamCalc results as well.
From all of this I still can not communicate what I do and why to others. Karl will know what I mean. Sergey believes it is impossible to train others to do what I (and other cut nuts) do, or to define to the level of automating the process.

With all the numbers I can reject a princess that has less than 90% of the two eyed tilting light return of a round. Or a cushion that has a table with too many/much of the black or dark zones you mentiioned above. Or a smaller spread than another comparable stone. etc etc etc

 

[LD]

Date: 4/25/2010 6:40:24 AM
Author: Garry H (Cut Nut)

Date: 4/25/2010 6:25:45 AM
Author: LovingDiamonds
I understand all of the above. However, there ARE consumers who don''t like the more perfect look of, say, a H&A diamond. Some that score highly don''t perform well in certain lighting situations and can black out. I would rather buy a beautiful diamond (irrespective of what the numbers say) without paying a premium. Perhaps I''m alone in that thought process but up until now I''ve never had to use numbers to buy anything and I don''t regret any of my purchases (or wish I had had more information at the start). What I found highly informative was when I was looking at asschers and Karl told me what to look for in terms of the cut itself (not numbers). That helped me to evaluate the diamonds I was looking at enormously. The numbers would have just blown my mind! This is only my perspective and I appreciate that I''m in the minority on this section of the forum but I still think it''s sad that people aren''t told to use their eyes more. Sorry!

Do not be sorry LD

I do both - I try to correlate what I see with the numbers.
I can not remeber the last time I saw a diamond with ok colour, clarity and transparency - where my interpretation of numbers and what I saw were in conflict.

It is now so much this way that using all the tools that I use (eyes, Ideal-scope, ASET if the stone is fancy shape (waste of time for rounds) and various types of light) - I prefer to have a good 3D model and DiamCalc results as well.
From all of this I still can not communicate what I do and why to others. Karl will know what I mean. Sergey believes it is impossible to train others to do what I (and other cut nuts) do, or to define to the level of automating the process.

With all the numbers I can reject a princess that has less than 90% of the two eyed tilting light return of a round. Or a cushion that has a table with too many/much of the black or dark zones you mentiioned above. Or a smaller spread than another comparable stone. etc etc etc

Thank you Garry. Most appreciated and I fully understand what you''re saying. I think some people have a natural affinity/feel for diamonds and their eyes steer them to the "best". From what you''ve said, you can "see" a great diamond so you purely use the other tools to confirm what you''re seeing. I believe that''s the way the numbers should be used i.e. look at diamonds, pick a few that you like best, then run them through the numbers to either back up your thoughts or highlight potential issues that may have been missed. Not the other way round. There''s a place for every tool when buying diamonds/gemstones but it''ll be a sad day when we rely wholly on technology to give us answers.

 

[risingsun]

One of the concerns that I have is advising--or being--the consumer who is making an online purchase. When I was in this position, the numbers and scans were very important to me. I couldn''t use my eyes until the diamond was delivered. I did use the vendor''s eyes and the appraiser''s eyes, along with with getting the best diamond [by the numbers/scans] that I could find. When I bought my next diamond at a B&M, I used the same approach. I had the advantage of seeing the stone and finding that the science and the beauty were a perfect match. I have had people come up to me frequently to comment on my diamond. They usually say that they have never seen a diamond like this. I know what they mean. I hadn''t either, before I bought my AGS 0 H&A diamonds. As a diamond novice, when I first joined PS, I needed education about diamonds. I received this knowledge on a level I could understand and use. I met B&M jewelers who were also able to add to my knowledge base. For me, I am grateful for the education I have received and I attempt to use it in an appropriate way.

 

[Karl_K]

Date: 4/25/2010 6:40:24 AM
Author: Garry H (Cut Nut)
Do not be sorry LD


I do both - I try to correlate what I see with the numbers.

I can not remeber the last time I saw a diamond with ok colour, clarity and transparency - where my interpretation of numbers and what I saw were in conflict.


It is now so much this way that using all the tools that I use (eyes, Ideal-scope, ASET if the stone is fancy shape (waste of time for rounds) and various types of light) - I prefer to have a good 3D model and DiamCalc results as well.

From all of this I still can not communicate what I do and why to others. Karl will know what I mean. Sergey believes it is impossible to train others to do what I (and other cut nuts) do, or to define to the level of automating the process.

I would agree with Sergey it is one of the reasons I have such a hard time writing asscher tutorials.
Much of it is tlr (that looks right)
Someone either has it or they don''t.

With rounds I could use DC to select them all day long cut wise, with fancies and step cuts in particular I don''t have that level of confidence. Maybe with the next generation of scanners it will get there.

 

[Garry H (Cut Nut)]

Date: 4/25/2010 9:09:04 AM
Author: LovingDiamonds

Date: 4/25/2010 6:40:24 AM
Author: Garry H (Cut Nut)

Do not be sorry LD

I do both - I try to correlate what I see with the numbers.
I can not remeber the last time I saw a diamond with ok colour, clarity and transparency - where my interpretation of numbers and what I saw were in conflict.

It is now so much this way that using all the tools that I use (eyes, Ideal-scope, ASET if the stone is fancy shape (waste of time for rounds) and various types of light) - I prefer to have a good 3D model and DiamCalc results as well.
From all of this I still can not communicate what I do and why to others. Karl will know what I mean. Sergey believes it is impossible to train others to do what I (and other cut nuts) do, or to define to the level of automating the process.

With all the numbers I can reject a princess that has less than 90% of the two eyed tilting light return of a round. Or a cushion that has a table with too many/much of the black or dark zones you mentiioned above. Or a smaller spread than another comparable stone. etc etc etc

Thank you Garry. Most appreciated and I fully understand what you''re saying. I think some people have a natural affinity/feel for diamonds and their eyes steer them to the ''best''. From what you''ve said, you can ''see'' a great diamond so you purely use the other tools to confirm what you''re seeing. I believe that''s the way the numbers should be used i.e. look at diamonds, pick a few that you like best, then run them through the numbers to either back up your thoughts or highlight potential issues that may have been missed. Not the other way round. There''s a place for every tool when buying diamonds/gemstones but it''ll be a sad day when we rely wholly on technology to give us answers.

Actually LD, i would go with the technology by choice over my eyes in most instances. But I do not use numbers at all - only as a rejection - e.g this round has 41.5pav and 36 crown - dont look. But never ever use #''s with fancies, ever!