HCA tool? How helpful is it when buying a diamond online?

[roxxx_m]

Looking for a diamond online.
Specifically on Blue Nile because I got approved for credit with them
So, I'm trying to find a great diamond. It makes it difficult because all the offer are the grading reports.
Staying with vs2 and above for clarity. I am however using the HCA tool, but I'm confused.

It states on the HCA tool that "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."


So is it safe to say that I'm better off with a score of 1.0 - 1.9 rather than 0.7, 0.8, or 0.9

Any type of help or opinions would be greatly appreciated

 

[diamondseeker2006]

Re: HCA tool? How helpful is it when buying a diamond online

You are rarely going to see an HCA score below .8. Most of the ones I see fall between 1.0 and 2.0. That is going to be your best bet if you have to buy from BN.

Here are numbers that will get you a favored HCA score and will generally fall within ideal cut specs:

table: 54-58

depth: 60- 62.3

crown angle: 34-35

pavilion angle: 40.6-41

girdle: thin, medium, slightly thick

 

[yssie]

Re: HCA tool? How helpful is it when buying a diamond online

Looking for a diamond online.
Specifically on Blue Nile because I got approved for credit with them
So, I'm trying to find a great diamond. It makes it difficult because all the offer are the grading reports.
Staying with vs2 and above for clarity. I am however using the HCA tool, but I'm confused.

It states on the HCA tool that "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."


So is it safe to say that I'm better off with a score of 1.0 - 1.9 rather than 0.7, 0.8, or 0.9

Any type of help or opinions would be greatly appreciated

No.

You're looking for a round, right?

HCA tells you only whether a stone is likely worth further investigation.
It does NOT tell you whether a stone is guaranteed to be a winner and it doesn't tell you that it'll be a doozy. Use it to narrow the field (depending on what specs you're looking for the field could be huge or relatively small) and "investigate further" to actually choose a stone.

What sort of stone are you looking for? Budget, size, colour..

 

[roxxx_m]

Re: HCA tool? How helpful is it when buying a diamond online

You are rarely going to see an HCA score below .8. Most of the ones I see fall between 1.0 and 2.0. That is going to be your best bet if you have to buy from BN.

Here are numbers that will get you a favored HCA score and will generally fall within ideal cut specs:

table: 54-58

depth: 60- 62.3

crown angle: 34-35

pavilion angle: 40.6-41

girdle: thin, medium, slightly thick

I've actually tried a few that rated as 0.8 - 0.9, surprisingly. But I also saw the most people prefer a stone that rates between 1-2 so that's why I'm confused I found a 0.70 Excellent cut round diamond with a score of 0.8 but I just pused it aside because I was unsure.

 

[roxxx_m]

Re: HCA tool? How helpful is it when buying a diamond online

Looking for a diamond online.
Specifically on Blue Nile because I got approved for credit with them
So, I'm trying to find a great diamond. It makes it difficult because all the offer are the grading reports.
Staying with vs2 and above for clarity. I am however using the HCA tool, but I'm confused.

It states on the HCA tool that "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."


So is it safe to say that I'm better off with a score of 1.0 - 1.9 rather than 0.7, 0.8, or 0.9

Any type of help or opinions would be greatly appreciated

No.

You're looking for a round, right?

HCA tells you only whether a stone is likely worth further investigation.
It does NOT tell you whether a stone is guaranteed to be a winner and it doesn't tell you that it'll be a doozy. Use it to narrow the field (depending on what specs you're looking for the field could be huge or relatively small) and "investigate further" to actually choose a stone.

What sort of stone are you looking for? Budget, size, colour..

Yes I am looking for a round diamond. Between 1/2 - 3/4 carat. It's for a ring. I or H color. And clarity wise, I decided to stick with either a VS2 or VS1 since I can't see the actual diamond online.

 

[diamondseeker2006]

Re: HCA tool? How helpful is it when buying a diamond online

Nothing wrong with .8 or .9!

Just narrow down your selection to stones that score 2 or less and then post them here for more feedback.

 

[roxxx_m]

Re: HCA tool? How helpful is it when buying a diamond online

So here's 2 that caught my eye:

Half carat Ideal
5.18 x 5.17 x3.18 mm

H

VS2

Excellent

Excellent

l/w ratio: 1.00

depth: 61.5%

pavilion: 56.0%

crown angle: 34.0

pavilion angle: 40.8

Girdle: Medium

HCA 1.0
---------------------------------------------------------------------------------------------------------------

0.60
5.46 x 5.43 x3.35 mm

Ideal

H

VS1

Excellent

Excellent

1.01

Depth: 61.5%

Table: 57.0%

Crown Angle: 34.5

Pavilion Angle: 40.8

Girdle: Medium


HCA: 1.4

 

[diamonds-are-friends]

Re: HCA tool? How helpful is it when buying a diamond online

these 2 look like they have good proportions.