Class IB cut Vs 3.5 HCA?

[glamgirl]

I am a little confused. Could a AGSO class 1B cut, with excellent polish and very good symmetry, and a score of 3.5 HCA be that much of a difference in brillance, and sparkle from an under 2 HCA. (or is the difference negligable) I am so confused as I keep reading that anything over 2.0 will look
noticably less sparkly, brillant. Does this mean ....beyond a doubt, that there will be light leakage? Could anyone explain how there might be an exception that these measurements would in fact NOT allow leakage in a handful of stones???

 

[pqcollectibles]

Have you seen the diamond yet, Glam?? There are exceptions to every rule. ALJDewey bought an absolutely fabulous 1.25 carat SI2 that is totally eye clean. Most SI2''s that size are not eye clean.

The HCA is just a screening tool. It is not etched in stone that any particular person will not like a diamond that scores above 2 on the HCA. The HCA just helps you weed out potential poor performers when buying sight unseen. The Vendor has told you the diamond is lively. The diamond business still runs on a person''s word and a handshake. A lie can ruin a 30 year reputation in the diamond business. The Vendor''s eyes are not yours and he/she may not see the diamond the same as you would. But, you may see a diamond with an HCA score of 1.5 and not care for the performance of that particular diamond. Diamonds are as unique as people are. Each has its own character and personality that was crafted by the cutter.

OK, I went back to your other post and took a look at the specs of the diamond you are considering. One thing I saw is the diamond you are considering is cut a bit deeper than the HCA "likes". The HCA program favors shallower cut diamonds. The diamond you are considering is a bit top and bottom heavy. Most Ideals have an average crown height closer to 15% with a pavillion depth less than 43%. The diamond you are considering has a 16.2% crown height and a 43.1% pavillion. Another thing is girdle. You didn''t post a girdle thickness. The HCA assumes the girdle is a particular %age average. So there are some "preferences" built into the program that impact the scores on diamonds that don''t fit the norm. It''s a combination of things that produce performance optics in a diamond. Even tho the HCA rates a diamond 3.5, the diamond can still have the right combinations to be a good performer.

Will the Vendor ship the diamond to an independent appraiser for a second opinion?? Let an independent expert take a look at the diamond and be another set of eyes for you. Another idea for you. Do you have a really good table shot pic of the diamond?? Post the pic and the stats again. Maybe someone will run a DiamCalc for you. They can use the wizardry of their nifty keeno software to tell you lots about the diamond with a good table shot pic.

 

[glamgirl]

Thank you for your thoughtful and gentle input! I have not seen the diamond. It will be arriving Friday or Saturday.
I did have someone (on pricescope) run the diamond cal, and it showed a white ring leak loss around the center table. I can tell you the girdle is thin to medium faceted. I have read (and heard jokingly) about this being the ring of death. When I asked about, what to expect with a 3.5 HCA, I had the sense the vendor wanted me to trust him, and not the number. I am spending alot..... as you can get an idea that even though I think the price is more than fair, its still alot of money, and I want to be sure, that light is very little light leakage, if 3.5 is a minimal negliable loss) I am ok ith it, BUT if it has a considerable difference, in the sparkle factor, then I will need to consider a different stone. Buying sight unseen, and not being able to compare is very very hard.

 

[pqcollectibles]

I haven''t seen the dreaded Ring of Death live and in person that I know of. I can honestly say that I don''t know if I would spot it right away or not.

Did the DiamCalc you got look similar to the one posted in this thread??

https://www.pricescope.com/community/threads/whats-wrong-here.6353/

If I understand correctly, you''ll see a slightly darkened ring under the table of the diamond. I''ll be interested to see if you notice it or not.

 

[Garry H (Cut Nut)]

HCA can not tell you for sure that a diamond under 2 is a winner - but it can tell you that there is a low likelyhood of a diamond of 3.5 being worth spending shipping and appraisal money on.

 

[glamgirl]

Yes. The diamond cal was very similar to this only the circle looked light pink,in some areas and white in others. The circle did not look pure white all the way around.

 

[glamgirl]

Your input is helpful to me. As I was going to get an independent apprasial from Nancy Stacy. So, it might be better to wait until it actually arrives, and then decide if I want to pay the extra for her apprasial. Could you tell me, based on what you have seen from excellent performers, compared to very good performers on HCA, if I had the stones side by side, is there a visual considerable difference, or would I have to look closely, and know what to look for?

 

[Garry H (Cut Nut)]

A dull darkish donut type area just inside the table
read this http://diamonds.pricescope.com/agsideal.asp

It would be far cheaper to buy an ideal-scope

 

[glamgirl]

So, if I buy an ideascope, to view the stone, would this help confirm the light leakage? Would I see this light ring around the center table? It sound like this would be helpful to me.

 

[Garry H (Cut Nut)]

Definitely.