Is as ASET still necessary for ideal cuts?

[plummiecat]

I have been shopping for a rbc in the ideal proportion range, GIA triple ex, and HCA less than 2. Is an ASET still needed?

 

[Christina...]

It's not necessary for AGS ideals because they are already evaluated for light performance, but GIA's range for excellent cuts is quite broad, so it's wise to get an idealscope. HCA is only a predictor and it only takes four angles into consideration, it should only be used to reject stones that are thought to be poor performers, the next step is an idealscope or aset.


edit:typos

 

[Dreamer_D]

No. In that situation you are on good footing to assume it is well cut if it passed both of those tests. There is a chance it is still not wel cut, and so an ideal scope image may be desirable, or your eyes comparing the diamond to others of known great proportions.

As an aside the term "ideal cut" only technically refers to stones with AGS0 cut grade. I mention this in case a vendor is using the term over-liberally.

 

[Paul-Antwerp]

I must agree with Christina, and disagree with Dreamer.

The GIA-grade and the HCA essentially are using the same methodology of a limited number of average angles, and there is little extra info from using both methods as opposed to only one. For more true info helping you in your decision, definitely an Idealscope-pic is necessary. The ASET on a round within a limited range might be overkill, but definitely get the Idealscope.

Live long,

 

[Garry H (Cut Nut)]

I must agree with Christina, and disagree with Dreamer.

The GIA-grade and the HCA essentially are using the same methodology of a limited number of average angles, and there is little extra info from using both methods as opposed to only one. For more true info helping you in your decision, definitely an Idealscope-pic is necessary. The ASET on a round within a limited range might be overkill, but definitely get the Idealscope.

Live long,

Total agreement