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snaphappy

snaphappy

Shiny_Rock
Joined
Mar 30, 2025
Messages
124
I have so many questions!! But AI is not really answering this one. So here goes.

On the internet, when I’m looking at brilliant round (assuming no leds are present) I see a lot of black, a lot of blue maybe, sometimes just in the center, sometimes the entire diamond.

Keep in mind, our diamonds are both in that j-m range, one is OEC and the other is transitional, both have culets.

So in the RBC am I seeing spears, or hearts and arrows?
Am I seeing D-I color and my eye is interpreting that as blue?
Am I seeing scintillation? And maybe old cuts like ours don't have scintillation because we don't have spears, or hearts and arrows?
Am I noticing this simply because the RBC has a MUCH bigger table than our diamonds?
Oh another question, does a culet stop this from happening?
 
Many of the colors in 360 video are enviromental.
Blue from shirts or uniforms is very common as is brown and yellow.

Many sites use a still shot of the 360vid for the static picture.
 
Last edited:
Ok they're not called spears. You guys call them arrows? I think the larger table allows me to see the arrows. And the arrows look black to me. I’m guessing the arrows are there in my wife’s transition cut, but maybe I can’t see them because the table is so small? Or the culet keeps me from seeing them? Or maybe both?

Here’s a video. Without perfect led lighting, all RBC diamonds look black and dark to me…

 
This in particular.
jointwire.gif
The reflection of the facets in red are the arrows. (pavilion mains)
In the oec they are the entire under table area.
They are cut to react to obstruction more in a modern RB than a cut for a ring oec or transitional.
If an oec reacted to obstruction and many do the same as modern RB they would appear dark in a ring at some distances.
However in a tiara or pendant they would be awesome.
The viewing distance is what changes and makes the difference.
Many videos are the same as viewing the diamond at 4-5 inches from your eye so obstruction is not representative.
 
Karl_K said:
This in particular.
jointwire.gif
The reflection of the facets in red are the arrows. (pavilion mains)
In the oec they are the entire under table area.
They are cut to react to obstruction more in a modern RB than a cut for a ring oec or transitional.
If an oec reacted to obstruction and many do the same as modern RB they would appear dark in a ring at some distances.
However in a tiara or pendant they would be awesome.
The viewing distance is what changes and makes the difference.
Many videos are the same as viewing the diamond at 4-5 inches from your eye so obstruction is not representative.


jointwire.gif
Click to expand...

Excellent explanation Karl!
 
I'm kinda slow. So bigger table = bigger obstruction? So my head is obstructing the light... and the table is bigger on the RBC... so it looks like a bigger dark area?

So if I view an RBC from across the room, with no obstruction, it will look magical? Interesting!

If I understand all of this correctly, it's perplexing that RBC dominates wedding rings. Hand is the only jewel you can obstruct so it seems like an odd place to put an RBC
 
I think your confusing video appearance with real world appearance.
In the video shown its a lighting issue not a diamond issue.
Someone would have to work very hard to ever see that diamond look like that to the bare eye.

A well cut RB has balanced contrast up close at a reasonable distance and not over responsive to obstruction at extended distances which makes them look less bright.
It is a balance.
 
Karl_K said:
I think your confusing video appearance with real world appearance.
In the video shown its a lighting issue not a diamond issue.
Someone would have to work very hard to ever see that diamond look like that to the bare eye.

A well cut RB has balanced contrast up close at a reasonable distance and not over responsive to obstruction at extended distances which makes them look less bright.
It is a balance.
Click to expand...

Maybe your right! I’ve never had one on my finger. Ok I need try one on haha
 
I have lots of questions. Here’s a new one. We noticed in direct sunlight our diamonds look dark. I reproduced this effect with a flashlight. It seems like direct light darkens diamonds. At the same time, when we turn off our bright overhead lights, and our room is lit by a single lamp, our diamonds turn white. My diamond in particular, which is much like a european cut, turns white in low light! Are these phenomena easy to explain? Seems so fascinating! Here’s some pics of my old diamond
IMG_9934.jpegIMG_9935.jpegIMG_9936.jpegIMG_9932.jpegIMG_9890.jpeg
 
snaphappy said:
I have lots of questions. Here’s a new one. We noticed in direct sunlight our diamonds look dark. I reproduced this effect with a flashlight. It seems like direct light darkens diamonds. At the same time, when we turn off our bright overhead lights, and our room is lit by a single lamp, our diamonds turn white. My diamond in particular, which is much like a european cut, turns white in low light! Are these phenomena easy to explain? Seems so fascinating! Here’s some pics of my old diamond
IMG_9934.jpegIMG_9935.jpegIMG_9936.jpegIMG_9932.jpegIMG_9890.jpeg
Click to expand...

That is a great indication of top cut quality.
Go to the very end of this long explanation of fluorescence please:

Fluorescence

As blue is the complimentary colour to yellow, the most common colour in diamonds, blue fluorescence can make yellow diamonds look white or colourless.
www.hollowaydiamonds.com.au www.hollowaydiamonds.com.au
 
Interesting! AI told me constant light from the sun does not allow any fluctuations in light in or out of the diamond. And sparkle and glow happen because of fluctuation. I think it might have mentioned contrast too. A pretty diamond means I’m seeing contrast, but full sun or a flashlight = no contrast
 
I read your whole article!! Brilliant! So much info. Do you have more articles? Or a book? Would be wonderful to read a whole book about this. I’m currently reading Stoned
 
Garry does have a book..... it's excellent !
1745424204434.png

Avail in Kindle or Paperback on Amazon
 
freddyboston said:
Garry does have a book..... it's excellent !
1745424204434.png

Avail in Kindle or Paperback on Amazon
Click to expand...

I usually prefer physical books, but the physical book is $57. You think the physical is worth it? Or just get the kindle for $10?
 
snaphappy said:
I read your whole article!! Brilliant! So much info. Do you have more articles? Or a book? Would be wonderful to read a whole book about this. I’m currently reading Stoned
Click to expand...

You could also look at past historical threads on Pricescope for discussions on cut. Many original members (including the posters who responded here, are professionals in that area so have posted many technical educational comments.

The book American Cut by Al Gilbertson is also linked for free in one of the threads. You can search. Paper copy is here, I’ve bought my own copy.
 
Garry H (Cut Nut) said:
That is a great indication of top cut quality.
Go to the very end of this long explanation of fluorescence please:

Fluorescence

As blue is the complimentary colour to yellow, the most common colour in diamonds, blue fluorescence can make yellow diamonds look white or colourless.
www.hollowaydiamonds.com.au www.hollowaydiamonds.com.au
Click to expand...

Also, here’s an informative thread Garry H once did on spot lighting (like a halogen light) turning diamonds dark.

I wonder if it’s not only fluorescence but modern-style ideal (low crown) cuts? that black out in spot lighting.

I think it’s two different things? 1) Blackout under spot lights which doesn’t require flourescence, 2) and Flourescence in sunlight or UV, turning the fluorescent stone dark blue

Garry H (Cut Nut)

Thread 'Why your diamond goes dark or blue in direct sunlight'

There has been another discussion about this topic, and the idea that Fluorescence plays a part. So I did a small test today with various different cuts.

20181224_105401-jpg.666325

Shaded daylight at 11am, close to the solstice, in Melbourne taken just now on 24th December. The shade is from my body. My hand was vertical and you can see me in the wedding ring and the blue cloudless sky. Its a hot day +30C 90F.
20181224_105443-jpg.666326

Note in direct sunlight the ideal-cut...
  • Like
 
snaphappy said:
Interesting! AI told me constant light from the sun does not allow any fluctuations in light in or out of the diamond. And sparkle and glow happen because of fluctuation. I think it might have mentioned contrast too. A pretty diamond means I’m seeing contrast, but full sun or a flashlight = no contrast
Click to expand...

That is pure hallucination!!!
 
Oh but one more question here, is it fair to say a RBC reflects more sky than OEC because the RBC has a larger table? And therefore an RBC would look darker in direct sun than an OEC?
 
snaphappy said:
Oh but one more question here, is it fair to say a RBC reflects more sky than OEC because the RBC has a larger table? And therefore an RBC would look darker in direct sun than an OEC?
Click to expand...

The order of impact:
Pavilion angle
Pavilion Main Length
Crown angle
Indexing
Table size
Girdle thickness
 
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