Betsy, the average diamond on the market doesn't even begin to look as good as this stone. Most diamonds will exhibit a significant amount of leakage either under the table or in the outer perimeter of the stone. Much, much more than those little white areas you see in the image.
It's pretty typical to have some white on the edge. The only stones that escape this are usually the super ideals which have had their minor facets "tweaked" to eliminate them, like the EightStar.
I've actually got two sets of data for your stone. One is using the pavilion angle listed of 40.8' and the other is using the pavilion depth listed of 42.9'. The reason I generated two is because the program indicates that a 40.8' pavilion angle would generate a 43.2% depth instead of the 42.9% depth listed. A 42.9% depth would be the product of a 40.6' pavilion angle, and would produce even slightly better results.
Either way, the stone's a screamer.
40.8' pavilion angle-
Light Return (mono)…...: 0.98 Very Good
Light Return (stereo)…..: 0.97 Very Good
(Non) Leakage (mono)..: 0.94 Very Good to Good
(Non) Leakage (stereo).: 0.94 Very Good to Good
Contrast............................: 0.98 Very Good
(Non) FishEye Effect…..: 1.00 Very Good
40.6' pavilion angle-
Light Return (mono)…...: 0.99 Very Good
Light Return (stereo)…..: 0.96 Very Good
(Non) Leakage (mono)..: 0.98 Very Good
(Non) Leakage (stereo).: 0.97 Very Good
Contrast............................: 1.00 Very Good
(Non) FishEye Effect…..: 1.00 Very Good
My guess is that your stone's performance falls somewhere in between these two analysis', which is great scoring.
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IdealScope- In general, the darker pink areas indicate areas of greater light return, with the lighter pink areas indicating areas of lesser light return. The black areas indicate areas of greater contrast, with the gray areas indicating areas of lesser contrast. The white areas indicate areas of light leakage. A good explanation of the IdealScope image along with examples can be found at https://www.pricescope.com/idealscope_indx.asp
Disclaimer- The facet arrangement and symmetry of the image will probably vary from your actual diamond, which may affect the light performance indicated. The computer generates an image with “perfect” symmetry, which is rare. Also, the star/lower girdle facet lengths may be different from your diamond. The computer simulation is reproduced best when the actual diamond is being viewed and the image "tweaked" to the appearance of the diamond, or Sarin info is downloaded directly into the program. However, this "blind" reproduction should be helpful in considering the major light performance aspects..
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