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ASET for antique cushion

Aurora26

Shiny_Rock
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Hi all,

I am considering an antique cut cushion and have received this ASET image for the stone. My understanding is that black is light leakage.
So my concerns after seeing this image is that 1) the cross facets are not high performing 2) that the area adjacent to the cross is “mushy”. Are these reasonable conclusions?
Please let me know your thoughts!
1590090015994.jpeg
 
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diagem

Ideal_Rock
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Looks like a modern cushion retouched, Kozibe hiding under big table. This is as far away from antiques as can be..., if Antique (genuine or real) is up your avenue, I suggest looking further..., plenty of options and few selected vendors offering such (decent cuts) today.

BTW, this is Aset white (white = leakage).
 

Karl_K

Super_Ideal_Rock
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In this case black is very deep obstruction or the center of the scope inside the blue area.
This stone could be stunning in a pendant but it will be blah in a ring.
 

Aurora26

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Looks like a modern cushion retouched, Kozibe hiding under big table. This is as far away from antiques as can be..., if Antique (genuine or real) is up your avenue, I suggest looking further..., plenty of options and few selected vendors offering such (decent cuts) today.

BTW, this is Aset white (white = leakage).

1590100255267.jpeg

Here is a normal image of the stone. I tried to understand Kozibe from a brief search but not sure I fully get it. Does this stone have that effect?
 

oldminer

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The black is reflection of the camera's black lens and its surrounding tubing. The diamond may be on a bit of an angle away from the perpendicular to the camera, too. The ASET image is very odd with the black zones. It was taken in an unusual way or possibly touched up.

Who knows? You may love the stone in person, but from what you have, I doubt you can be sure.
 

Aurora26

Shiny_Rock
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In this case black is very deep obstruction or the center of the scope inside the blue area.
This stone could be stunning in a pendant but it will be blah in a ring.

The black is reflection of the camera's black lens and its surrounding tubing. The diamond may be on a bit of an angle away from the perpendicular to the camera, too. The ASET image is very odd with the black zones. It was taken in an unusual way or possibly touched up.

Who knows? You may love the stone in person, but from what you have, I doubt you can be sure.

Thank you both for sharing your knowledge. The image provider came back and responded “The white areas are your main leakage and the black areas are more blocked than anything” and “Black/blue areas are not necessarily a bad thing to see in the image, as long as you do not see them stay that way in the video. The main thing you want to avoid is large areas that do not change whether they are lit up or dark.”

To conclude, now less sure this is a stone I’d want to pursue.
 

Karl_K

Super_Ideal_Rock
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The regular picture gives a pretty good idea based on the ASET what you would see, large dark areas in a ring environment when static. The overall effect is a less bright appearing stone because it is looking for light in areas your blocking it.
At long distances in a pendant they come to life.
 

Aurora26

Shiny_Rock
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The regular picture gives a pretty good idea based on the ASET what you would see, large dark areas in a ring environment when static. The overall effect is a less bright appearing stone because it is looking for light in areas your blocking it.
At long distances in a pendant they come to life.

Could you give a little explanation on what’s going on with the areas where light is “blocked”? As just a commoner, I’m not quite grasping the concept - what would be blocking light from reaching those facets?
 

Garry H (Cut Nut)

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Thank you both for sharing your knowledge. The image provider came back and responded “The white areas are your main leakage and the black areas are more blocked than anything” and “Black/blue areas are not necessarily a bad thing to see in the image, as long as you do not see them stay that way in the video. The main thing you want to avoid is large areas that do not change whether they are lit up or dark.”

To conclude, now less sure this is a stone I’d want to pursue.

The explanation from the vendor is accurate.
Can we see the video?
The Koxibie effect is when you see the culet thru the crown facets. Some love it some do not.
I will slightly disagree that the black (oOld Miner descrbed it correctly) is from dead centre of the viewing position.
It likely turns to red for each eye and is only dark when one eye is closed.
It could be an additive brilliance effect. What we call binocular rivalry.
 

Karl_K

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Could you give a little explanation on what’s going on with the areas where light is “blocked”? As just a commoner, I’m not quite grasping the concept - what would be blocking light from reaching those facets?
You are, when your looking at the stone.
That area of the diamond is looking for light right back at you when your looking at it.
 

Karl_K

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I will slightly disagree that the black (oOld Miner descrbed it correctly) is from dead centre of the viewing position.
only place it could come from in the ASET image is dead center in the scope????
 

Garry H (Cut Nut)

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only place it could come from in the ASET image is dead center in the scope????
I made 2 nailhead diamond videos Karl - one with ASET which has a wide blue section.
1590122963864.png
Another with Gilbertsonscope which has a smaller black zone
1590122998967.png
But no where near as small as the hole that was drilled into this ASET Scope causing a very very small dark zone.

https://youtu.be/Mm2SMhXFgqs

 
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diagem

Ideal_Rock
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1590100255267.jpeg

Here is a normal image of the stone. I tried to understand Kozibe from a brief search but not sure I fully get it. Does this stone have that effect?

Hi, in short, the kozibe effect is when an opened (e.g. polished vs. pointed) culet gets reflected through all or most crown facets when viewed from the top.

I dont know if I am allowed to post a link to an educational I wrote about this subject as its from our website, Andrey feel free to remove if not allowed.
This article explains about the History of the open culet (Kozibe): https://gemconcepts.net/diamond-kozibe/

I attached this image which clearly presents some attributes of antique cuts, you can notice a much taller crown (e.g. girdle to table) which automatically requires larger crown facet surfaces creating a much smaller table.The the diamond in this picture is slightly tilted and show how all the open culet reflections (e.g. kozibe) are capturing light and reflecting back to the viewer.
Kozibe_on.png

Not sure if you like this phenomena as Garry mentioned its not everyone's cup of tea but if you do, the antique cut cushion you posted doesn't possess or reflects such attributes.

Good luck,
 

Tanukiko

Rough_Rock
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In this case black is very deep obstruction or the center of the scope inside the blue area.
This stone could be stunning in a pendant but it will be blah in a ring.

I know this post is super old but I came across it and had to say this statement confuses me. In a ring the observer can either be the wearer or an observer. If it will be awesome as a pendant to the observer it will be awesome in a ring to the observer as well. The wearer need only look at the ring in a mirror to see it’s beauty since observing it directly will show those dark black reflections.

or yes…wearer could wear a head lamp. Lol
 

Karl_K

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I know this post is super old but I came across it and had to say this statement confuses me. In a ring the observer can either be the wearer or an observer. If it will be awesome as a pendant to the observer it will be awesome in a ring to the observer as well. The wearer need only look at the ring in a mirror to see it’s beauty since observing it directly will show those dark black reflections.

or yes…wearer could wear a head lamp. Lol
The difference is the viewing distance.
The degree of obstruction varies greatly with distance and a pendant is viewed at a much greater social distance than a ring.
It is not generally socially acceptable to view a pendant at 8 inches on someones neck and if someone is that close they are not likely interested in just seeing a diamond.
 
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