Trust HCA over eyes?

[BryanJA]

Hi all,

I''m trying to decide between two stones, both round F VS2 2.02 or 2.03 carats:

Diamond A B
Weight 2.02 2.03
Color F F
Clarity VS2 VS2
Fluor. N N
Table 58.5% (58.2-58. 57.5% (56.9-58.1)
Depth 61.8% 61.6%
Crown angle 34.1 (33.9-34.2) 34.7 (34.0-35.5)
Pavil angle 41.7 (41.5-41. 41.1 (40.9-41.3)
Crown height 14.6% (14.3-15.0) 14.5% (14.2-14.
Pavil Depth 43.8% (43.4-44.4) 43.1% (42.8-43.3)
Offcenter:
Table 0.4% 0.2%
Culet 0.1% 0.3%
Girdle: M 1.5% (1.2-1.9) Sl. Thick. 2.0% (1.4-2.3)
Proportion 1 0
Diameter 8.15 (8.12-8.1 8.12 (8.09-8.15)
Polish G EX
Symmetry VG VG
HCA 5.9 2.8

So, I''m inclined to trust the HCA and go with diamond B, but comparing them side by side, A seems to produce white light more evenly -- there seems to be about half of diamond B that is a little bit dark. They both seemed about as ''sparkly'' (but what do I know???). Perhaps unfortunately, I''m an engineer so I''m inclined to trust numbers over eyeballs, especially my own. But I know there are smarter people than me hanging out here... so, what should I do??? Can HCA be this far off, or was I just not looking for the right things? Am I crazy? Price is about the same.

Thanks a bunch, (and, of course, the sooner you can reply the better)
Bryan

 

[pqcollectibles]

Actually, your eyes are probably not failing you. Something about the performance of one diamond held your eye while the other didn't.

Rhino from GOG recently went thru a detailed explanation about a Brilliance Scope on a particular diamond. He explained, pic by pic, how the cut could affect the actual performance. Here's the link to that thread:

https://www.pricescope.com/community/threads/b-scope-results-help.12785/

While this explanation may not be directly applicable to the performance you observed, hopefully this will sorta help explain what you saw in person.

 

[anothernewbie]

I trusted the explanation of Rhino et. al and turned that diamond down.

 

[Mara]

Hmm interesting...I definitely like the numbers on the 2nd stone better. Plus VG/EX vs G/VG etc.




But if your eyes think they saw something in the 2nd one that you don't like, and they both appeared as sparkly? Hard to really say. Can you keep looking until you find something where both the numbers fit AND the stone looks amazing?