Idealscope intrepretation

C04Whitmer · Apr 14, 2004

I''ve heard a ton about idealscopes and how you can see light return with them, but how do you intepret them? Obviously the red areas are light return, white are not. I have yet to see what a "good" princess idealscope image looks like, if anyone has one please upload it! Let me know what you think of the picture of my prospective diamond

The diamond is:

1.01 carats

D color

VVS1 clarity

72.4% depth

68% table

9.9% crown

42º crown angle

60.1% pavillion

56.9º pavillion angle

Thin to medium girdle

VG Polish G symmetry

No cutlet

~$6K

/idealbb/files/Idealscope 1 carat princess.jpg

pricescope · Apr 14, 2004

Let's look at it from historical angle.

People discovered that a lot of leakage (white color) is bad because these areas do not reflect back and you even can see thru the diamond.

They decided then the less leakage the better. I think it is another extreme.

Small areas with partial leakage still can return light and add to the diamond contrast. There is no evidence that people will prefer a look of a diamond with no light leakage comparing to a diamond with limited light leakage.

Example: shallow round brilliant has even less light leakage than Tolkowsky ideal but will appear darker from close distance.

Round diamonds with shallow crown have little light leakage and are brighter but may have less contrast and fire.

This image definitely shows leakage in some areas. On another hand it doesn’t leak as much as an overage princess, which cut for weight retention. It still can be a nice stone.

I would approach it like this: weed out obviously bad stones. Let your own eyes see and compare remaining candidates (or ask an expert to do it for you).

Hest88 · Apr 14, 2004

Garry has a picture of very good light return on the fancy shapes Idealscope page.

http://www.ideal-scope.com/fancy.asp

valeria101 · Apr 14, 2004

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On 4/14/2004 11:52:39 AM C04Whitmer wrote:

Let me know what you think of the picture of my prospective diamond

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Hm... pass.

Scintillation and contrast are great, but why not achieve contrast with intense red and black? The white is there, the hot red is not.

There is no standard interpretation of Iscope images for fancies, but it would help to look at a bunch of stones for which both IdealScope and BrillianceScope are done. A couple dozen of such exampels resite at GoodOldGold (both 'for sale' and among the 'educational diamonds').

My attempt to interpret these images made me believe that regardless of wether white areas are present or not (not a bad thing if they are there, as Leonid explains), it is the presence of dark red and especially black spots that throws the Brilliance scope rating high up for all three scales. Of course, this is an amateur interpretation and very 'second hand' to boot - since I did not have the opportunity to also handle all those diamonds and get an artistic impression of them.

The stone in the picture has about the same mix of white and light red I woud expect form the Iscope of an olminers cut (these I do know first hand). The image guarantees mediocre light return - and could mean good scintillation. At least the old cuts deliver lots of fire to compensate - but I am not at all sure a princess cut will do that. Yikes!

And the disclaimer, of course: no, this is not an ugly diamond... all these scope' stuff is relative and limited. It is better to take stone in hand and look at it... if you can!