0.46 or 0.5 carat stone

[pml003]

Hello:
I have learned a great deal from reading the forums.
A few questions:
I am looking at a 0.46 H SI1 Ideal H&A AGS
and a 0.52 I VS2 "Ideal" GIA

about same price, will the I color look yellow in a plat setting even if it is an ideal cut? Will a 0.46 look small compared to a 0.50 diamond?
What diamond do you recommend, the 0.52 is bigger and clearer, but an I; the 0.46 is not as clear but whiter and a better cut.

Thanks alot

 

[Garry H (Cut Nut)]

there is a loose correlation between weight and size.

We need more info - but the 1/2ct is a better deal, because it IS a 1/2ct.

 

[fire&ice]

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On 7/25/2002 7:15:35 PM

there is a loose correlation between weight and size.

After a vast and extensive search, we just purchased a 3 ct. round brilliant stone of very good cut. One thing that I found interesting is how important it is to look at the measurements when dealing w/ a large stone. While I knew the cut would affect the size, it surprised me that within the same cut parameters the measurements varied. Why is that so? I would suppose that the girdle thickness would be a variable. Would the culet size be a variable also?

And, yes to quote (I believe) Leonid ,personal preference does enter into the equation when purchasing a stone. I personally prefer a deeper stone (61-62%. Call me crazy, it just looks richer to me). And, (except for the cut - which is ultimately paramount to what a diamond should look like) appearance of the stone is most important. My stone on paper should not be as pretty and bright as it is. Mine is I, SI1, 59% table 62% depth. When I went to view the stone even my jeweler/appraiser (he was getting paid regardless of what stone I picked) said he was impressed at how "pretty" the stone looked. The stone faces up to at least an H color and said he thought a G. It does have med. blue flour (Again, going against recommendations - I'm a big fan as long as long as it doesn't look oily- all my stones have it,even my family ring of old european cut- once again personal preference).

On another intersting note. The cert is an EGL - my appraiser is a GIA trained Gemologist and told the dealer that he would grade as such and don't send the stone unless it would hold up to GIA standards. Well, my jeweler said the stone was leaning more toward an H color when compared to his master set. The clarity, however, did not hold up - it was more of an SI2 - but we thought the price reflected such. Ultimately, it is eye clean and contained no feathers (which bothers me - again personal preference). At the end of the day, while it is what it is, the stone is very pretty. I am under no illusion that this stone was an investment. I just wanted a big pretty rock to wear and pass on to the family to enjoy when I am gone. ..just my spin on it. I would, however, recommend when purchasing a stone of size (.75 and above) to always seek an independent appraisal - to, at the very least, know what you are getting. My jeweler said the biggest problem he finds when appraising stones are fracture filled or laser drilled stones. I am by no means knowledable in this field. I would consider myself informed though. I read Cuellar's book "How to Buy a Diamond". While the book offers some sage advice, I went against a majority of his "rules". I think I lost faith in the book when I reveiwed the "secret" wholesale pricing charts. I found the prices to be "off the charts". And, quite frankly, was surprised that he had such a strong opinion on Flourescence. I agree about a green or yellow Flour; but, as stated before, I like blue flour as long as it doesn't make the stone look oily or milky. Maybe I'm looking at it from a consumer's point of view. I would love to have other's perspective on this.

 

[pricescope]

Fire&Ice, thank you for sharing your story!

I'm impressed by the research you've done and your confidence.

Blue fluorescence is beneficial for I color diamond - makes it looks whiter.


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While I knew the cut would affect the size, it surprised me that within the same cut parameters the measurements varied. Why is that so? I would suppose that the girdle thickness would be a variable. Would the culet size be a variable also?
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Relationship between crown and pavilion angles also affects the measurements even if all other proportions are the same. Do you know crown and pavilion angles for your diamond?


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And, yes to quote (I believe) Leonid ,personal preference does enter into the equation when purchasing a stone.
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Don’t refer to me – Garry thinks I have a weird taste

 

[Garry H (Cut Nut)]

The effect of each Proportion factor on spread is quite surprising. This is for the common variances in the market comparing to a Tolkowsky ideal Girdle Ext thin 0.92ct Ext thick 1.19ct = 27%
Crown
28 degrees 0.92ct
40 degrees 1.08ct
= 16%

Pavilion
41% 39.4„a 0.97ct
50% 45„a 1.09ct
= 12%

Table
53% 1.00ct
70% 0.92ct
= 8%

does this make sense?
Can you see that with just table and depth % there is the possability for many variations in spread.

 

[Garry H (Cut Nut)]

Quirky - not weird Leonid

and not always bad taste - but sometimes a little extreme in regards the strength of opinion - eg I dislike Vegas
Leonid hates Vegas!

 

[fire&ice]

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On 7/26/2002 11:16:49 AM


I'm impressed by the research you've done and your confidence.


Thanks, but the confidence also lies in my "jeweler". I had a unique situation in that I have been buying & selling to him for about 15 years. So, I was given some professional courtesy. His primary focus is estate jewelry, which is a passion of mine as well (I actually looked for a large european cut stone; but the larger stones of quality in the 3 ct range are far and few between)

I do say, that had I not had this situation, I would seriously consider buying an internet stone.

Blue fluorescence is beneficial for I color diamond - makes it looks whiter.


Wondering if anyone read the study the GIA did on fluor? ...very interesting. Again, I'm a big fan!


Relationship between crown and pavilion angles also affects the measurements even if all other proportions are the same. Do you know crown and pavilion angles for your diamond?


No, really bought on my eye. In my search, I noticed that a stone may have better "ideal cut" table & depth % and did not have the life my stone has. So, I am beginning to see the important relationship of crown angle & depth pavilion. The faxed copy of the cert was not clear - fax machine was on a feeding frenzy - kept crunching the paper. I just purchased the stone this week and the dealer was to mail the cert to my jeweler - I will know then. The measurement were approximately 3.02 ct- 9.25 x 9.19 - forget off the top of my head. I was actually more interested in what my jeweler thought than the cert. It looks better in person than on paper - a pleasant surprise! Finally told hubby that I was 8,000 below my budget. He's impressed. ...now I have extra to spend on the setting

 

[fire&ice]

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On 7/26/2002 7:49:11 PM

The effect of each Proportion factor on spread is quite surprising. does this make sense?
Can you see that with just table and depth % there is the possability for many variations in spread.

This is fascinating - geez...sounds like you really do have to do the math!! How accurate are the crown angle & pav. angle readings. The reason I ask is that I have two appraisals for my engagement ring (purchased twenty years ago). Both readings are different (and yes, they are the same stone). I was really only interested in a piece of paper for my insurance company.
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[pricescope]

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How accurate are the crown angle & pav. angle readings.
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Today many cutters and grading labs are using Sarin or Ogi machines that optically measure the proportions of the stones with accuracy up to 0.1 degree.

 

[fire&ice]

Thanks...sound like technology at work. The stone has not been appraised in over 10 years.

I am assuming that all stones are still cut by hand. Is this tradition and will never change? One would imagine w/ all these laser cut intruments in medical science that diamonds could be cut that way

 

[pricescope]

, cutting machinery is very precise these days.

Moreover, there are different machines and software that allow to calculate the best way to cut a rough diamond.
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