Sarin and HCA questions

[nethead]

I have been shopping around with retailers and the internet for an engagement stone. Based on the sage advice of the wise men and women who kindly contribute to this forum, I asked for a Sarin report on a diamond I am considering for purchase given the lack of info on the GIA.

The Sarin report gave ranges in parantheses for the crown (35.3-35. and pavilion angles (41.0-41., but also gives single crown (35.5) and pavilion (41.4) angles. I understand that these angles will vary around the diamond, but I am wondering how the Sarin software arrives at the values. I assumes it takes a number of measurements and averages. Or are the angle numbers produced by a somewhat arbitrary picking of 2 points and average just those 2? The single number values look light they may be based on only 2 angle measurements.

Does this mean that the single angle numbers produced by Sarin may not tell the whole story? If so, wouldn't this affect the accuracy of the HCA report? After all, garbage in, garbage out.


The specs on the diamond I am considering are as follows:

GIA cert
6.21-6.24 x 3.83 mm
.9 c
F
SI1
vg vg faint
ht: 61.5%
depth: 58%
crown angle: 35.5
pavilion angle: 41.4

The price is $3,600. It doesn't score all that well on the HCA, showing brilliance as very good but fire as only fair. I don't need the best in every category, but would like something that will still look great. Any opinions as to whether I am getting value for the money or I might be sacrificing too much on cut would be appreciated.

By the way, the site and forum are great. Kudos to you experts for helping us lost laypeople find our way in the byzantine world of diamonds!

 

[nethead]

The ranges again: crown angle is 35.3-35.8 and pavil angle 41.0-41.. I don't know how the faces got in there.

 

[wndrful]

You are sacrificing on cut. But I see your point that you might not want the best cut. And you are willing to give up a little on cut but get better at something else. Its give and take. I understand.

Just make sure that its eye-clean SI1.

Plus its personal. But I rather stick with the best cut over anything else. I suggest compare the diamond with say a smaller diamond with really good cut and similar price. Take a look at it in different lighiting condition. Buy what you like.

 

[pricescope]

Sarin gives you measurement of pavilion mains and crown kite facets.

Pavilion facets are more important because the light is reflected twice from them.

 

[pricescope]

An average angle between opposite pavilion facets is also very important.

As you can see from this Sarin picture, one main has 41.4° angle but the opposite one has 40.0°. It is 40.7° in average, which is just fine.

 

[pricescope]

Nethead,

This diamond has a reasonable price but it also has steep/deep combination of crown and pavilion angles. HCA doesn't like it because the diamond should have noticeable light leakage under the table. Besides, it has smaller spread, i.e. looks smaller for its carat weight. 0.9 crt Tolkowsky cut stone has 6.28 mm in diameter.

If you want more light return from your diamond you could try to find a diamond with shallower crown.

 

[Garry H (Cut Nut)]

Well answered floks.

For the record, the table of this diamond is probably on a slight tilt and because the table is the reference plane - all other angles are out relative to it. This need not be a big problem, but the proportions are lousy. Kepp looking

 

[nethead]

Thank you all for your comments. Just wondering, though, would an average Joe like me actually be able to tell the difference between this cut and something that might score say a 2 or 3 on the HCA?

 

[pricescope]

Only you can answer this question. Experts do it easily. Some consumers can too when compare different diamonds side by side.

The best way to see a difference is in a dim light environment (candle), not in jewelry store or day light.

If you don't see a difference, there is no point to pay premium for an ideal cut. On another hand, HCA can help you select nice looking stone outside of traditional "ideal" range and save some $$.