How important is spread in HCA ratings?

[schu]

I''m looking at a diamond that ranks .9 on HCA with everything being "excellent" except for spread with is "very good." From what I have gathered you want an HCA score to be sub-2 and nearest to 1.

So what is spready and how does it effect a diamond?

 

[jet2ks]

Date: 9/1/2009 3:13:02 PM
Author:schu
I''m looking at a diamond that ranks .9 on HCA with everything being ''excellent'' except for spread with is ''very good.'' From what I have gathered you want an HCA score to be sub-2 and nearest to 1.

So what is spready and how does it effect a diamond?

HCA only gives Excellent in spread to diamonds under 60.3% depth. Most really well cut stones will get a Very Good there, so nothing to worry about. A shallower proportioned diamond that has more face up size for its weight has a greater liklihood of other issues, such as obstruction or lack of fire. There has to be a trade off somewhere.

As far as score, HCA is an elimination tool only. Diamonds scoring under 2 are worth further consideration via performance images, photos and live examination, but a score near 1 is not necessarily better than one that scores 1.9.

 

[Laila619]

Date: 9/1/2009 3:26:28 PM
Author: jet2ks
HCA only gives Excellent in spread to diamonds under 60.3% depth. Most really well cut stones will get a Very Good there, so nothing to worry about.

I was wondering why every diamond I plugged into the HCA tool only had a ''Very Good'' for spread! Now it makes sense.

 

[stone-cold11]

Not necessary you can''t get all Ex in the HCA just rare.

For example this.
http://www.jamesallen.com/diamonds/F-VVS1-Ideal-Cut-Round-Diamond-1218735.asp

 

[schu]

Thanks jet. This whole diamond buying thing is unnerving, especially browsing online (not like I''d know what to look for in-store either).

Maybe you can shed some light on whether or not this is a good stone.

Round Brilliant
Measurements: 7.48 - 7.54 x 4.59 mm

Carat Weight: 1.55 carat
Color Grade: G
Clarity Grade: VS1
Cut Grade: Excellent
Proportions:
Depth: 61.1%
Table: 55%
Crown Angle: 34.0°
Crown Height: 15.5%
Pavilion Angle: 40.8°
Pavilion Depth: 43.0%
Star length: 50%
Lower Half: 75%
Girdle: Thin to Medium, Faceted (2.5%)
Culet: None
Finish:
Polish: Excellent
Symmetry: Excellent
Fluorescence: None

Holloway Cut Adviser
Light Return: Excellent
Fire: Excellent
Scintillation: Excellent
Spread: Very Good
Total Visual Performance 0.9 - Excellent within TIC range

The only thing I have for this diamond is the GIA report (attached) but they do not have any other imagery. So how do you know if the diamond is worth purchasing at 16.5k without much to back up the price. I have seen a few vendors have detailed images online, but most do not.

 

[stone-cold11]

Numbers looks good.

 

[stone-cold11]

Do you really have to buy from this vendor?

I can find same specs for much better price...

 

[jet2ks]

Agree with Stone Cold that the numbers look good. Is this with an online seller or a brick and mortar store? You can use the Pricescope your diamond at the top of the page to compare this stone to what some others would charge for a similar one.

If you can''t get performance images, and still want to purchase, then all you can do is make sure to examine the diamond during the return period in a variety of different lighting environments to see if you are happy with it, or buy your own Idealscope.

 

[stone-cold11]

For example.

http://www.jamesallen.com/diamonds/G-VS1-Premium-Cut-Round-Diamond-1259328.asp

 

[schu]

I forgot to mention that it is labeled as a H&A. That being said, I''m not married to the vendor, I just liked their ability to allow me to pay via installments. I have the money now, but with the market performing so well for me I''m hesitant to pull my money out and miss what could be some continued big gains.

The JA prices look pretty good. I just sent them a feeler to see if they charge MD sales to MD customers since they are partially based in this area. If they do, adding on another 6% will put their prices back up with other vendors.

 

[stone-cold11]

Request for a Hearts image if the stone is sold as a H&A stone.

For the JA stone, request for an Idealscope image. This is not the cheapest stone I found on JA, just the 4 EX HCA score, there are a few of other stones, slightly lighter but still over 1.5c, and H&A and still cheaper.

So go and take a look if JA do not charge tax for MD.

 

[Lorelei]

This diamond has great potential, however as it is purported to be h&a then images of both hearts and arrows are needed in order to prove the overall cut precision required of these diamonds.