HCA is not based off gary's opinion
it's based off proportional ratio between the crown and pavilion angle with acceptable range of depth and table against it.
"An Ex/Ex/Ex/VG is in no way worse then a Ex/Ex/VG/VG which scores below 2. They just have different characteristics."
Wrong, there is a high chance it can be worse.
The HCA was developed to aid people to simplify acceptable ranges. Just like how all the different labs have their acceptable ranges of what ideal and excellent is, not only JP looks to a lower HCA, even ACA whiteflash has scores below 1.5
you are right to say a 1.7 may not look bad, but there is a higher chance than something below 1.5, and given most consumers are not experts, companies with super ideals do their filtration for them. bluenile signature carries a wide variety of 0.3 to 2.5 and up HCA scores, that's because they don't want to narrow their range too much.
ex/ex/vg/vg means that you have a diamond leaning towards fire than scintillation.
simply put, a score below 1.5 has the higher chance of the best combination of fire and scint.
It is based on proportions, yes, but like i mentioned, it is based on his opinion because of the way the weightage is assigned. It is weighted to the look he likes and not all elements are given equal weightage, and this is a fact. Once within the 0-2 range, different numbers have different characteristics, and are not better or worse
On the HCA page it self, it says this in bold...
"A score below 2 (Excellent) means you have eliminated known poor performers (more than 95% of all diamonds).
Your own personal preference may be for a diamond with an HCA score of 1.5 more rather than one with a lower score of say 0.5.""
On both the HCA site and his own personal website he says...
"
Most people prefer stones that rate 1-2 on a scale where: 0-2 Excellent, 2-4 Very Good, 4-6 Good, 6-8 Fair, and 8-10 Poor. Zero is almost impossible since many of the factors conflict."
These seem to obviously indicate that not lower is better, else he would simply say lower is better and not use the ranges/examples he used. Using it in a lower is better method is using it as a selection tool, not the use it was intended for.
With regards to the EX/EX/EX/VG and EX/EX/VG/VG, it is the same misuse of the HCA as a selection tool. Gary confirmed that this is NOT the case as recently as last month . And says once again that the HCA is a rejection tool, not a selection tool (people misuse it in this manner VERY often). He also goes on to say that ranges up to 2.5 or 3.0 could also be acceptable (i believe this is to accommodate his penalization of steeper and deeper cuts based on his opinion during the creation of the HCA). Most people normally accepts what the creator of the tool says...
Not sure what having stones under 1.5 proves... given the number of ACAs of course there are stones under 1.5, just as there are stones with 2 and above... Check out the Whiteflash ACA page... once again, the white flash ACA favors the 34.9/40.9 cut as i have mentioned before. Over half their stones have numbers close to this, even up to numbers like 35/41. Enter 34.9 and 40.9 in the HCA and tell me what you get. I get 1.7. Is my browser screwed up ? If it is not, then over half of their stone scores over 1.5... Some of the ones with higher numbers even score 2 or 2.1... an example of HCA's penalization of slightly steeper/deeper cuts. So does their super ideal looks worse ? It does NOT. It is simply the look they are going for, and also a number within the range of both the Tolk Ideal and Morse Ideal (sadly ignored by most consumers).
PS: After your last posts about the lower halves i also checked with Jon and he verified that there IS more contrast due to the lower girdle halves, the angles play a part, and the stars while not affecting the hotspots will affect other parts of the diamond which may affect contrast. And the increased contrast is not a visual illusion...
For the O.55 one how come the hearts look flawed? Is it a alignment problem of the diamond when taking the pictures? anyway the 0.53 hearts alignment at the 5O'clock looks a bit off.
If the spots on the diamond of the 0.55 one is just alignment then go for it!
O_O Duno, who said that. I thought the 0.55 looks better then the 0.53, did i miss something ? Hahaha. To me for the 0.53 the obvious issues are the number of uneven V and the difference in sizes of some of the hearts, like how small the 7th heart is compared to the 8th. The 0.55 definitely looks alot better to me.
But i agree, if its just an alignment issue, I would prefer the 0.55.
they say I waste money. Cannot understand what they thinking. Old folks theory is the bigger the better, the rest like color clarity doesn't matter, don't mentioned the tripple E. Sad to be trashed by them
