How do you obtain the data for your cut estimator when most James Allen diamonds only provide the GIA certificate upon request? Just by browsing JA, I can only do a visual check for optical symmetry but I guess would have to request a certificate for each diamond to check the GIA/IGS cut per your cut estimator. Thanks!
I use computer vision to automate the visual check you’re doing for optical symmetry. I built a classifier to predict whether it’s AGS 0 Ideal just based on its appearance. I think it does a better job than just going by the proportions, because AGS 0 Ideal does not guarantee that the arrows are strong and crisp.
If you were shopping in-person, you would first find a diamond that looks nice and then maybe use the report to corroborate your observations. Online shopping has put the cart before the horse, where people now look at the paper before looking at the diamond. Looking at the images first restores the proper order. You buy with your eye, you don’t buy the paper.
No, I would not have second thoughts. I’d trust my eye over the certificate and go with the great optical symmetry. That’s why in my write-up I say “Our ‘false positive’ diamonds with 36.5/40.6, 36/40.8, and 34/40.6 crown/pavilion angle combinations typically show stronger arrows and have better optical symmetry compared to the ‘true positive’ AGS 0 Ideal diamonds with 41.4 and 41.6 pavilion angles that our classifier ignores.”
Very interesting, thanks. And what a fantastic and helpful write up. Do you consider the AGS ideal angle and table proportion ends in themselves? Would you have second thoughts about a diamond that has great optical symmetry (the arrows) but doesn’t fall into the AGS ideal range?