Diamond Scope Question ??

[NPtheBruin]

I was hoping that someone could run a Diamond Scope/Other test on this stone and give me your thoughts. Any help would be GREATLY appreciated:

Weight: 1.68
Color: G
Clarity: SI1
Flourescence: Med Blue
Diameter (mm): 7.70 (7.69 - 7.72)
Crown Angel: 34.5%
Crown Height: 15.1%
Pavillion Angle: 40.8%
Pavillion Depth: 42.9%
Cutlet : 1.6%
Table Size: 55.8%
Total Depth: 61.4%
Girdle Thickness %: .5 - 1.4%

Thanks so much for your help!

 

[Mara]

Rich? Anyone?

 

[niceice]

Girdle thickness of 0.5% thin is dangerously thin in our opinion... Culet size seems a bit large... Other than that, the proportions look good... Don't need the DC2 to tell you that the diamond should be "kicking" but if it makes you feel better, here you go:

Mathematical ray tracing results:

Note that this does not mean that the diamond isn't leaking light... Just that it isn't leaking light at this particular vantage point, as the diamond is rotated leakage would become apparent at various angles and from specific facets - this is true of all diamonds...

Simulated / computer generated / estimated firescope image:

 

[Mara]

Very nice simulated image. I also wanted to note that this stone scores a 1.2 TIC on the HCA with EX EX EX VG and no subtractions made for the culet (put it in with 0 and then with 1.6 and it did not change the score). The girdle is a little thin, but insurance can take care of that!

 

[Garry H (Cut Nut)]

Hey guys did you see one of my earlier posts - there has always been that detail missing in the parametric ideal-scope images compared to real 3D Sarin scaned modeled Ideal-scope images - and the code breaker is inside the options>advanced>lighting config> Sim parameters (expand) >ray tracing for round and then change 2 to 4.

 

[Garry H (Cut Nut)]

oops
did not do the out of round!

Sorry Rich - to much good Aussie wine

 

[NPtheBruin]

Thanks for the replies, very helpful.

Would any of you mind commenting further on the two issues that were brought up: Girdle thickness, and cutlet size

Girdle thickness -- too thin -- what are the implications of this? Is it likely to chip/fall out? What will insurance do for me?

Cutlet -- too big - what are the implications? Just waisted weight?

Thanks so much for your very insightful comments/analysis.

 

[Garry H (Cut Nut)]

Do not set it in a high prong ring or it may chip. If you insure it as Mara says - it is then the insurance companies problem.
The culet is not a problem. It is about the same size as the width of A4 paper and would be very hard see.

 

[NPtheBruin]

I'm pretty sure I know the answer but ... does the attached constitute a high prong ring? what are chances of chipping with this setting...

 

[Mara]

As long as you get it insured I wouldn't worry and just set it into the setting you prefer. Our stone has a higher risk of chipping and the setting head is somewhat high, somewhat like you posted. I had wanted it a little lower, so I was a little worried, but we insured it and now I figure...oh well! If it chips accidentally, the insurance covers the full amount, so we are set.

If you are not planning on insuring it, then you should try to minimize the risk of chipping in a lower setting or a bezel where the metal surrounds the girdle..or maybe even a tension.

Also it bears noting that your girdle range is .5-1.4 meaning that at some point around the stone, the girdle is .5 which is very thin. But unless you get a detailed report showing the highs and lows of the girdle so you can actually see where it is thinner, you will not know where that .5 thinness is or if its just one spot or more. Chances are it's just one area that is that thin...while the rest may range from .7-1.4 which is more acceptable. The range is a range of the entire girdle, so take it with a bit of a grain of salt. It most likely does not mean that your entire girdle area is 'extremely thin'.

Good luck!

 

[Rhino]

Gary that is a great sim image and very similar to what I observe in my analysis and photos. More similar than the images I was able to generate within DiamCalc.

In another thread you mentioned to change it from 2 to 6. Do you think 2 to 4 is better? I'll have to play.

Rhino

 

[Garry H (Cut Nut)]

Rhino 4 is good and quicker.

NP the stone should be set down the bottom, and ask for the thin part to be put near prongs to reduce the exposure to blows. As Mara says - the insurance will do the rest

 

[Garry H (Cut Nut)]

Rhino 4 is good and quicker.

NP the stone should be set down the bottom, and ask for the thin part to be put near prongs to reduce the exposure to blows. As Mara says - the insurance will do the rest