Light Leakage

[me1234]

I looked at a 2 ct with pavillion angle of 41.4 under a firescope and saw very little light leakage, yet, I am being told that this is too steep of a pav. angle. Why wouldn''t I see the leakage?

 

[pricescope]

Me1234, Try to get other proportions of the stone: crown angle, table size, total depth, girdle, and measurements along with exact carat weight.

Pavilion angle alone is not enough to discuss cut quality and leakage in particular.

Did you use original Firescope with 8* dealer?

 

[me1234]

Leonid-
1.95ct G Vs2
61 depth
58 table
33.9 crown angle
41.4 pavillion angle
no flouresence

It's getting a poor HCA score, but looked good under the firescore. Yes, it is an 8* dealer, why?

 

[pricescope]

Diamond with 58 table, 33.9 crown and 41.4 pavillion angle should have leakage under the table similar to one shown on this Diamond Calc. simulation.

What are the measurements?

What is the source of these data (Sarin BrilliantEye or Diamension, AGS report)?

There also might be a problem with viewing light leakage with latest models of Firescope.

 

[me1234]

The source was from the Sarin report. I didn't get the measurements. I'm not too familiar with the firescope, but does this picture shows lots of light leakage?

 

[me1234]

Based on what I've noted, should this be a diamond I should even consider? I'm looking to spend around $14K.

 

[pricescope]

Of course you can consider any diamond if you like it and the price is right.

Try to get measurements though. Does the diamond has GIA or any other grading report? Measurements should be cited there.

 

[me1234]

It is GIA. Why did ask about the 8* dealer?

 

[Serg]

P 41.4 Cr 34.5 has very big leakage
P 41.4 Cr 33.5 has not big leakage

Cr 34 is on the boundary.

 

[pricescope]

What one should consider big or small, Serg?

These are subjective terms.

These DiamCal evaluations for the data above.

 

[Serg]

----------------
On 8/5/2003 5:12:10 PM leonid wrote:

What one should consider big or small, Serg?
----------------

Leonid,

You may not see the influence of a weak leakage within usual lighting.
The influence of a strong leakage is easily seen even with usual lighting.
If this definition is not objective enough for anyone then he may measure the leakage by percentage of people who are able to see the influence of the leakage with usual lighting conditions (there are serious reasons why this way is not possible to use for leakage estimation with special lightings like IS, FS)

 

[Serg]

P 41.4
Cr 33.5/34.5

 

[Garry H (Cut Nut)]

This might be the difference Leonid is referring too.

Of course without having the full 3D proportions of the stone we cannot produce a perfect model.
Note the greater leakage with the ideal-scope.