Help on cut of diamond

[Loengard]

Hi all,

I''ve just gotten the specifications of two diamonds that interest me (both round brilliant cuts). They are both EGL (Antwerp) certified.

Diamond 1
- Carat: 1.23c
- Colour: G
- Clarity: VVS2
- Measurements: 6.83x6.80x4.25 mm
- Proportions: very good
- Depth: 62.3%
- Table diameter: 60%
- Crown height: 15%
- Pavilion depth: 43%
- Girdle thickness: medium
- Finish grade: very good
- Fluorescence: slight

Diamond 2
- Carat: 1.47c
- Colour: G
- Clarity: VS1
- Measurements: 7.23x7.17x4.55mm
- Proportions: very good
- Depth: 63.1%
- Table diameter: 59%
- Crown height: 16%
- Pavilion depth: 43%
- Girdle thickness: medium faceted
- Finish grade: very good
- Fluorescence: slight

What do you think of both diamonds, in particular of their cut?
Also, should I be worried about the slight fluorescence (will it show)?

Thank you so much for your advice,
Peter

 

[cmcwill]

I ran the specs in the cut advisor at the top of the page...they did not turn out so well

4.0 for the first and 3.6 for the second. I would read up on some threads discussing rounds and learn how the HCA measures cut performance. It is a guideline, not an absolute, but a pretty good guideline!

Colleen

also, I wouldnt be worried about slight fluorescence... may help the G (already white) look even whiter!
vvs2 might be overkill on clarity...try to go down a notch and up in cut quality!

 

[Nicrez]

I agree with Colleen, that these stones don't WOW me. They are cut too deep, making you pay for carat weight that deadens the stone's brilliance, and that you don't get to see when hidden in the setting!

Usually for round stones, the magic dimensions around here are a depth around 60-61% and a table of about 55-58%, seems to be the average. Of course getting the pavillion and crown angles help a person determine how it will rate (numbers wise) with brilliance, fire, scintillation and spread. If you can, go see them in person!

 

[valeria101]

So... the HCA says 'good buy if the price is right' and so they are..

Both have larger tables - and this is likely what throws the HCA overboard. Neither havs no blatant issues to talk about ("fish eye" comes to mind). Both get "Very Good" scores for light return and get hit in the fire department

So... basically I would expect, two bright white stones, rather large for their weight (esp. the first) which show some serious flash when turned at the right angle (which the ring on a hand does all the time, esp. for 'showing') and tend to turn off the light engine when looked at from close-by (when shadowed by the person looking at them) or the surrounding light source is not strong (say, candle light).

Are these ungly

, of course not.

Better balance between fire and brilliance can definitely be provided by a bit different cut proportions.

Fluorescence would not be an issue to me (although it is healthy to keep in mind it sometimes is a pricing factor).

 

[Giangi]

EGL Antwerp is known for its liberal grading. You may want to run a search to see what most of us think about it. I would be worried that those G's may actually be H or I and VS 2 clarity.
That being said, the cut on those doesn't have a ''wow'' effect on me. Probably they are two attractive stones, but the crown seems to be pretty steep and it's not coupled with a shallower pavilion ( I would have preferred to see something like 60% 15% 42% on the first and 59% 16% 42% on the second, if the crown has to be that high.). You can tell they are not extremely well cut by the diameter of the 1.47ct... it measures 7.20mm in average, while a well made 1.47ct should be about 7.4mm.
So, to sum up... Are these pretty? Yes. Are these the best (or one of the best) I can get? No.
But before worrying about the cut, I would make sure the grading is fairly accurate.

 

[valeria101]

In fact... I'd call on stone No.2 - it is so close to the 'FIC' ideal range that I may well choose to see the full half of the bottle here.

The current averaged out Sarin measures tax this stone on fire, but it is closer tot he 'fiery brilliant' range than anything else.

It would be a safer bet to get a known H&A stone and rightfully expect top optics than hunt down these exceptions to the rule, but if there is no rush - it does not cost a fortune to get to look at a particular stone. If #2 turns out to live to it's promise, it would probably be a good deal over a H&A with the same specs - if that particular color and clarity combination is what most makes sense to you.

Hope this makes sense...

 

[valeria101]

This is what I was trying to spell out above.

Not that the original score is a reject (it says "very good" - right?), but the reality could be better still. There is plenty of room for measurement error and such in that 1% variation, for better or for worse.

The first stone is way further from the 'truth' - and no chage of it's give measures within the believable error level of those numbers would make it 'sound' better.

This logic does fringe on overinterpretation, but one may want to take into account that these stones did not receive the precise cutting of those H&A pieces, so surprises are likely - both bad an dgood ones...