Need help - Are these loose diamonds any good?

[plumfairy]

Hi guys,

I need some help determining if any of these 2 loose diamonds is worth buying.
I am based in Australia and the diamonds will be purchased from a local retailer who buys them from their head office in Asia - only able to decide whether it's a buy or no buy through the GIA reports provided.

The local retailer has provided me with 2 options:

Option 1
Measurements 6.41 - 6.44 x 4.02 mm
Carat Weight 1.01 carat
Color Grade E
Clarity Grade VS2
Cut Grade Excellent
Depth 62.5 %
Table 57 %
Crown Angle 35.0°
Crown Height 15.0%
Pavilion Angle 41.4°
Pavilion Depth 44.0%
Star Length 50%
Lower Half 80%
Girdle Thin to Slightly Thick, Faceted, 3.5%
Culet None
Polish Excellent
Symmetry Very Good
Fluorescence None
Clarity Characteristics Feather, Indented Natural

Option 2
Measurements 6.56 - 6.59 x 4.11 mm
Carat Weight 1.10 carat
Color Grade F
Clarity Grade VS2
Cut Grade Excellent
Depth 62.4 %
Table 59 %
Crown Angle 35.0°
Crown Height 14.5%
Pavilion Angle 41.4°
Pavilion Depth 44.0%
Star Length 45%
Lower Half 80%
Girdle Medium to Slightly Thick, Faceted, 4.0%
Culet None
Polish Excellent
Symmetry Excellent
Fluorescence None
Clarity Characteristics Crystal, Feather, Pinpoint

Thanks for your help.

 

[D_]

Nope.
Stone 1 scores 4.9 on HCA, #2 5.3
If buying stone sight unseen try to use the HCA tool https://www.pricescope.com/tools/hca and look for those which score 2 or below.
You didn't mention the price. Quality aside it'll be helpful to know if the prices are fair.
If you are only going to buy a diamond based on GIA stats only, might as well go through the online route IMHO, cut 1 more middle person in the process.
Try using the diamond search function above.

 

[plumfairy]

Nope.
Stone 1 scores 4.9 on HCA, #2 5.3
If buying stone sight unseen try to use the HCA tool https://www.pricescope.com/tools/hca and look for those which score 2 or below.
You didn't mention the price. Quality aside it'll be helpful to know if the prices are fair.
If you are only going to buy a diamond based on GIA stats only, might as well go through the online route IMHO, cut 1 more middle person in the process.
Try using the diamond search function above.

Thanks for your feedback, D. I've looked at the HCA and read write-ups that say that although some stones have HCA>2, they are not entirely bad stones if other xx and/or yy criteria complements it (eg. crown angle and pavilion angle).

So if I'm looking at stones, is it safe to say that I should consider stones with HCA<2 and anything >2, I shouldn't bother?

Both stones are quoted at about AUD$10K.

 

[ecf8503]

The GIA excellent cut category is very broad - too broad - and it lets in some not-so-good excellents. That's where the HCA can be helpful - it weeds out some of the poorer performers. If you insist on buying only by the numbers without any light return images to help you, then yes - try to stay with an HCA under 2. The two stones you listed both have CA/PA of 35/41.4, which is steep/deep and it will face up smaller than it should for it's weight as well as having less than ideal light return. Doesn't matter what the polish/symmetry are if the angles aren't complimentary.

 

[D_]

I've looked at the HCA and read write-ups that say that although some stones have HCA>2, they are not entirely bad stones if other xx and/or yy criteria complements it (eg. crown angle and pavilion angle).

So if I'm looking at stones, is it safe to say that I should consider stones with HCA<2 and anything >2, I shouldn't bother?

Both stones are quoted at about AUD$10K.

Complementing angles would be 35/40.6 or 34/41.
I find this chart helpful btw https://www.agslab.com/docs/pbcg/AGSLProportionCharts.pdf

If you can see the stone in person then you have your own eyes to judge the beauty of the stones, diamonds w/ HCA>2 can be pretty.
Since you are buying blind, it's generally safer to pick those w/ HCA<2, like ecf8503 said.
Price seems fair, more towards the lower end.

 

[plumfairy]

The GIA excellent cut category is very broad - too broad - and it lets in some not-so-good excellents. That's where the HCA can be helpful - it weeds out some of the poorer performers. If you insist on buying only by the numbers without any light return images to help you, then yes - try to stay with an HCA under 2. The two stones you listed both have CA/PA of 35/41.4, which is steep/deep and it will face up smaller than it should for it's weight as well as having less than ideal light return. Doesn't matter what the polish/symmetry are if the angles aren't complimentary.

Thanks for your comments, ecf8503. I have declined both the stones and am back to the drawing board

 

[plumfairy]

I've looked at the HCA and read write-ups that say that although some stones have HCA>2, they are not entirely bad stones if other xx and/or yy criteria complements it (eg. crown angle and pavilion angle).

So if I'm looking at stones, is it safe to say that I should consider stones with HCA<2 and anything >2, I shouldn't bother?

Both stones are quoted at about AUD$10K.

Complementing angles would be 35/40.6 or 34/41.
I find this chart helpful btw https://www.agslab.com/docs/pbcg/AGSLProportionCharts.pdf

If you can see the stone in person then you have your own eyes to judge the beauty of the stones, diamonds w/ HCA>2 can be pretty.
Since you are buying blind, it's generally safer to pick those w/ HCA<2, like ecf8503 said.
Price seems fair, more towards the lower end.

Thanks for sharing the chart, D. I will keep looking for ones with HCA<2.

 

[decisively_unsure]

Stone 2 could be a stunner, but too much of a risk without seeing it in person. Better to stick to safe numbers.