Confused about HCA score

[hellosisi1977]

Is the lower HCA score the better?
I know that below 2 will be excellent. However, is there any limit on the lower bound?
Among 0.8, 1.3 and 1.8, (All are GIA ex cut or AGS 0), Are there any preferences?
Thanks!

 

[scepture]

The HCA is an elimination tool. If a score is under 2, the general consensus is that this a stone that is worth further investigation. If you can get an ASET/IS image to look at, that will always beat out an HCA score. The lower the score (so long as it is lower than 2) does not mean it is 'better' than another stone just because it is closer to 0.

 

[kenny]

I agree.

Reject rounds that score over 2.0.
If it scores under 2.0 the next step is to get an Idealscope image. https://www.pricescope.com/tools/ideal-scope

Compare it to this reference chart: http://www.ideal-scope.com/1.using_reference_chart.asp

 

[Rockdiamond]

If one is going to use the HCA, the lower the score, the better.
Many individuals will actually prefer a stone that scores higher ( worse on the HCA)- so it's use is by no means a universal thing.

I'd advise looking at stones in person, the plug them into the HCA to see how they correlate to HCA scores.
Some of my very favorite stones score over 4 and 5 on the HCA- all were purchased in person though.