Opinion on Radiant

[verticalhorizon]

Shape: Radiant
Carat: 0.96
Color: D
Clarity:VS2
Depth: 75.8
Table: 74
Girdle: M
Polish: Very Good
Symmetry: Very Good
Culet: None
Fluorescence: No
Measurements: 5.43-5.38X4.08
Length/Width: 1.01

It leaves off the crown heigth. What would a good matching crown height be for this rock?

Thanks!

 

[pqcollectibles]

Bump

 

[valeria101]

Ok, I am puzzled... what should be the respective crown height 'good at' to be desirable for you?

The stone is rather deep and this allows the table % to also be quite large without getting bigger than the depth number.

There are at leats two cut standards on the radiant; AGA's and the numbers describing the original Grossbard's radiant. The are not really in conflict - at least regarding square stones like yours, and at a first glance the AGA seems more strict. Both standards fall short of saying "these numbers insure good light return"-as you know.

According to either standard, this stones appears to have some shortcommings. The AGA gives it a 3A score, provided that the crown height goes as high as 16-17%. I do not know weather these numbers take into account the LxW ratio of the stones... Grossbards' standard goes to great length to comment on how measurements have to be adjusted to account for the rectangular shape, but all those numbers say is that your stone should have been bigger (LxW= ~34 square mm), with both depth and table smaller (depth between 55%-69%, table 58%-69%)

I sometimes end my posts with 'hope this helps'. I am not at all sure this can help, but at least I might have demonstrated how tangled the issue is. And I suspect your stone can still shine it's way through nicely.

PS:
The mentioned charts can be found at: RadiantCut and AGA

 

[verticalhorizon]

Great info. Thanks.

So is it safe to say that the Table% sould be less than the Depth%?

Also what about this term called Windowing? With a larger table, is this stone more suceptible?

Thanks again!

 

[valeria101]

Windowing is more of a threat in colored stones - diamonds very rarely appear with a 'window' and you would need extremely shallow stones for this; the table size is not the critical parameter for windowing.

A shallow pavilion and large table does other things - such as limit fire (the difraction of light reflected from the pavilion facets). This is just one argument for the rule of thumb that the table% should be less than the depth%. This is not to be applied bliendly (for example, I would not consider very desirable a stone with, say, 80% depth and 79% table). The tables quoted above contain a serious doze of common sense for consideration...