Need fast advice on 62% table diamond!

[Mara]

We are considering the following diamonds, from a local 'connection' very reputable jeweler that we had originally met through my best friend (they are her family's jeweler and she worked there in HS). We have history as well with Jeff, but wanted to wait until we had more research under our belt before calling him. So call him we did, and I told him what we had narrowed it down to (the 1.27 E SI1 that I asked advice on this forum earlier this week), and asked what he could do to compete with that.

He brought in two diamonds, which we viewed today. They are both beautiful and both score under 2.0 on the HCA. They are both 1.23/1.24, but one looks significantly larger, because it has a diameter more suited to a 1.4-1.5 carat diamond. It was very interesting, the table was 62%. In my searches, I haven't come across a diamond with such a large table--and immediately in my mind I struck this diamond from the 'serious' running. However, I was wrong. The diamond looks bigger due to the spread, and sparkles very well. BUT when set next to the regular 1.24 diamond, they both looked gorgeous, but the larger diameter one looked a little 'darker' inside of the diamond (don't know if this might be because its a G color and the other one was an E, so very white?).

Anyway enough babbling--here's the heart of the post. I ran them both through the HCA with their crown and pav angles, and was pleasantly surprised to see that both scored under 2.0, with the regular 1.24 scoring 1.0 TIC and the larger diameter one scoring 1.4-1.7 BIC(using both angles and % I got the range). My questions are:

1- What could the darker look inside of the large diam diamond be? Or is that just my imagination while comparing them both together side by side?
2- What's the difference between 'fiery' and 'brilliant' cuts. I ready the HCA comments but they didn't really settle the matter for me. Is BIC more sparkly than a TIC?
3- Should I worry about the large table at all? The depth is 56.9 and the table is 62%. Between the two diamonds, the regular one looked slightly more sparkly, but the large diam of the other one paired with its very good sparkle and great pricing makes it more desirable.

Here are the two diamonds info for your FYI. I also like that the larger diam one is a VS1 and extremely clean, because while the other one is very sparkly, it has a noticeable large dark crystal (though this can be set under a prong).

#1:
6.81x6.88x4.30mm
GIA cert
1.24 carat, E, SI1
depth: 62.8%
table: 56%
pav angle: 40.6
crown angle: 35.3
girdle: medium to slightly thick
culet: non
polish: VG
sym: G
fluor: none
HCA score: 0.9-1.0 TIC
price: $7200

#2:
7.15x7.19x4.08
GIA cert
1.23 carat, G, VS1
depth: 56.9%
table: 62%
pav angle: 41.1
crown angle: 29.9
girdle: thin to medium
culet: none
polish: VG
sym: G
fluor: none
HCA: 1.4-1.7 BIC
price: $7200

There is also a 3rd diamond we are considering, but its an online purchase. It sounds perfect ,but we have not seen it. Here are basic specs (dont have them all with me)

1.27 carat, E, SI1
AGS 000
polish: ideal
cut: ideal
sym: ideal
HCA score: 0.4 TIC
price: $7200

Sooooo I guess..knowing all of this..which to choose? My local jeweler can only keep these another day or two before returning them, so we need to make decision soon--which is fine. We are leaning towards the larger diameter one for a few reasons. We like the look of it (e.g. spread is excellent), and the color is still very good at 'G' while clarity is excellent. The price is EXCELLENT, very similar to the lowest prices found online at a reputable site, and we know this jeweler--we can continue to build a relationship with him by making the purchase. Also there is the opportunity for a trade-in later if we want to. However, the online diamond's 'paper' certs look stellar and the HCA score is superb. But we can't see it before we buy it--though we can have it sent to an independent appraiser before purchasing.

So if the experts could please weigh in, it would be great. I'm a little concerned about the slightly darker appearance of the larger diam diamond, but overall we love that one mostly because of its visual play with size. Is this good? Thoughts?

Thanks, I appreciate any comments. This is tough!
Mara

 

[diamondsman]

Those are not bad measurements for the stones!
I think you should check out the prices on the net and compare to see if you are getting a good deal!

diamondsman
www.buydiamonddirect.com

 

[diamondsman]

Sorry forgot to mention that the one with a table of 62% should a flat stone, and it is not because of the table , it's the depth that makes it flat.


diamondsman

 

[pricescope]

Mara,

You did wonderful homework

62% table is a bit large but if crown and pavilion angles are right the diamond still look very nice as you noticed. Plus you have better spread as a bonus.

I plugged proportions for #2 into Diamond Calculator and it shows dark area under the table as well. You also have to be careful with 29.9° crown angle. Diamonds with low crown angles have higher risk of chipping.

Trade discounts such diamonds more. Price for #2 is 19% back while for #1 only 10% back from list.

Sorry, I cannot tell you which one you should buy – both have pros and cons

 

[pricescope]

----------------
Sorry forgot to mention that the one with a table of 62% should a flat stone, and it is not because of the table , it's the depth that makes it flat.
----------------


Diamondsman,

Diamonds with larger tables usually have lower crown height, don't they?

For example.
Crown angle: 34.5°
Table size: 56%
Crown height: 15.1%

Same crown angle but 62% table size - Crown height: 13.1%

In order to get crown height back to 15.1% for 62% table the crown angle should be 38.5° which is rather steep.

 

[Mara]

Thanks for the info, leonid. I'm so glad I'm not going crazy..no one else could see the darker area but me. What IS that darker area under the table, and is it due to the cut? From Diamond Calculator, can you tell if that affects sparkle or brilliance at all? Also, do you know what the difference is in the appearance between a BIC and a TIC..should a BIC be more sparkly?

Also one of my concerns as well with #2 is that once we set it, it may lose its brilliance, what are your thoughts, knowing the specifics? If we get it, should we keep it in more of a floating setting to let more light get at it or is that not necessary? Will the setting help protect it from chipping due to the shallow crown if we get a specific type? We are setting it in platinum, don't know if that will help.

And lastly, you mention 19% off list for the #2 diamond with the large table, what is list specifically? Is the price we are being quoted a good one for this stone or should we try for more off?

Thanks, I appreciate it very much!!! I am very torn on this actually, and have no idea what to do. Both diamonds yesterday looked beautiful, but I want to be sure we are getting a good deal and the fire in the stone will still be fine when set. The online stone seems perfect, but now my boyfriend will be harder to convince because he liked both stones from yesterday. I may just let him make the final decision, as I am way overstressed!

Mara

 

[pricescope]

does it look like this?

 

[pricescope]

Here is another DiamCalc print screen for #2. Nothice very littel light leakage and quite good light return in the Cut Evaluation tab

 

[Mara]

Thanks for the pictures, leonid. The diamond does indeed look similar to the first picture, with somewhat of a grayish look in the middle, but it was hard to pinpoint--the overall picture to me was just that the diamond looked slightly darker inside than the other one we were looking at. My boyfriend also recalls the diamond seeming more sparkly towards the edges--though he maintains that to him they both sparkled THE SAME. So again, what does the darkness in the table mean? Not great reflection of light? If so, why does the HCA rate it as a BIC, and the diamond calculator pictures you showed with light return/leakage rate it well as well? I guess I'm a little confused as to what the darkness in the table really means amidst all the numbers. Also when set, will we loose some of the light from the sides, or ? I'd asked a few other questions in my 2nd post as well, please let me know if you know the answers to those.

Thanks--again I appreciate the time very much!!!

 

[pricescope]

to play with Gem Adviser [/u]

 

[pricescope]

I believe it is reflection of the observer' head. Let's address HCA questions to Garry.

This stone should not loose anything when set. That shouldn't be your concern.

 

[Mara]

In response to Serg's post...which somehow moved UNDER mine..Hmm it's way too early on a Monday for me to try to interpret all the technical speak. The jist of it as I got it is that there might be different reasons for the blackness in the table, and some of which could be light reflection from the light source, or an innate lack of light, or the angle the diamond is being viewed at. Did I get it? Or some of it? Interesting chart, it looks like my diamond lays in the 1.9 yellow area of the chart..is this a good thing?

Leonid, thanks immensely for posting the file for me, I did download Gem Advisor the other day and had no files to play around with! Now I have my very own potential diamond to look at. I appreciate all the info, now we just have to make a decision.

If anyone else cares to weigh in with their two cents, I would appreciate it.

Also, Garry for the HCA results??

 

[Serg]

I see no problem that there are diamonds having flashes on pavilion mains on the photos made with inclined position. There are a lot of such diamonds. Besides there are diamonds showing flashes on pavilion mains even without incline. Nevertheless there diamonds that cannot show flashes on pavilion mains without incline and there are diamonds that even cannot show such flashes even with great incline (if the light source is located in the upper hemisphere of the diamond)

The problem is in the interpretation of the black zones in the Ideal-Scope, Firescope.

There are 2 kinds of black zones (for a while I suggest to discuss the diamonds position without incline and at fixed distance from observer).

The first kind will be always black with no dependence on the light sources location.

The second kind can have any color and intensity and it depends only on the light sources location.

The quantity of these zones depends on the diamond cut parameters. There are a lot of such zones for the diamonds from the red area of Nail Head chart (see below).

The problem of the interpretation of black zones observed in the FScopes is that we cannot distinguish the first and second kind of those zones (good and bad) using these tools.

Now about the incline. The black zones of the first kind consist of 4 classes. These classes have different incline stability. The black zones of the first class (classical NailHead - pav 45’ - horizontal line on the chart) are very stable against the incline. Zones of other classes have less incline stability i.e. there is such incline value with that we can see source reflection in that zones. The incline value also decreases if the cut parameters lie in the class boundary on the chart (yellow color).

The modern ideal cuts usually lies on the boundary between yellow and green color (i.e. they have few amount of first kind black zones and only small incline is needed to make them change their type or even become red in the FireScopes)


Does my explanations help or even makes all that more complicated?

 

[pricescope]

I already emailed Garry to comment on this thread.

I think it is interesting case of the nice looking diamond that traditionally would be considered as off-make.

Keep in mind that the file and the pictures are simulations only for perfectly symmetrical stone. You can use them to analyse potential light return and leakage but the real stone might be different.

 

[Mara]

Here is an attached picture of the actual large diameter diamond being discussed on my hand. I wasn't angling it to catch the light very well though...but you can see some of the sparkle. Also its on the wrong finger, as the 'fake ring' he was using to hold the diamond for me was too big for my actual ring finger. The pic is a little blurry, I am still figuring out how to take close-ups with my new digital cam.

Comments?

 

[Garry H (Cut Nut)]

Off to work - no time to read it all - but this shallow crown stone is out because it will chip.

 

[pricescope]

----------------
Off to work - no time to read it all - but this shallow crown stone is out because it will chip.
----------------


Doh! All the efforts in vain!

 

[Mara]

That does sound quite negative, but I am going to be persistent and ask a few more questions on this stone.

I have read in posts on here and in other areas that anything under 30 degrees for a crown angle is where the ice gets a little thin (ha ha?), and even on the GIA cert this diamond is noted for the shallower crown angle under 30. However, if this is a 29.9 angle it's .10 under the 30 mark AND it has a thin to medium girdle. Does this give it ANY hope of not chipping?

Also, how do you know a diamond will chip and does the setting or metal used have anything to do with it? I am going through older posts that somewhat address this issue, but would like more info from Garry (if he gets a chance!) or others before we completely throw this stone out of the running. We were about 95% sold on it before that last post..now ??

 

[Mara]

Oh and came across this written by CutNut in a previous post:

'You could try asking for shallower crown angles say 30-33 and pavilion ANGLES around 41- 41.3 with table sizes of 55-62%. (shallow crown combined with deeper pavilion and vice a versa. Run a few combinations thru HCA and you will get the idea.'

Again--if this crown angle is 29.9 which is right under the shallowest end of 30, and the pav angle is 41.1, doesn't that still fit in the 'okay' region of things?

Lastly, if Garry says to discard the diamond because of its shallow angle/ability to chip, why does the HCA say that the cut is a BIC in the excellent range? Does the HCA not take into consideration the crown angle shallowness?

 

[Mara]

Okay my boyfriend has taken matters into his own hands (and after reading all the posts, etc and listening to me talk incessantly about diamonds for a month straight), and is calling the jeweler this minute to tell him we want the larger diameter stone.

I spoke with the jeweler a little while ago, and voiced my concerns on shallow crown and the dark center, and he said that in his 32 years of owning his own store and before that being the VP of Zales etc etc he has seen less than 1/2 of 1% of diamonds chip with a crown angle such as this. Also he suggested we get the insurance we got for the stone cover chips just in case if we were super concerned.

On the darkness in the table he said it was an angling of the pavilion facets and the size of the table creating a slight darkness.

Overall, between the two stones we were considering, they are both the same priced, he said he and his wife both would choose the larger tabled one as it has more character and is a great buy for the $$ while still being extremely well cut.

So I guess that's it!!! I appreciate all the comments, assistance and help, and hope we made the right decision!!!

(it all seems very anticlimactic?!)

 

[tonysgeko]

Mara, may you let us know how your diamond reacts to different kinds of lighting? Lighting such as fluorescent, halogen, incandescent, sunshine(direct and under the shade), lighting inside the car at night, and my personal favorite clear x-mas lights .

 

[Garry H (Cut Nut)]

OK here goes Mara.

Well done on all your research.

The darkness varies for different people because:
1. Different head / hair sizes block more illumination.
2. Different distances of prefered viewing.

If it is darker for you I suspect that you focus closer up and / or have a larger hair coffuire than your man?

You caan read all about this on Sergey's and Yuri's website in a ground breaking article written maybe before you were born, and only recently rediscovered.
http://www.gemology.ru/cut/english/faceting/

The girdle is thin to medium. If it were slightly thick I would have no concern about the chipping. Insurance and setting in a rubbed in bezel would fix that worry though

This is a good exaample of a stone that scores well on HCA because of spread. Spread is a desirability factor - not a quality factor. My experiance tells me that people like spread

 

[Garry H (Cut Nut)]

This is the most recent HCA that also has a girdle thickness calculation. This is about a thin to medium girdle and you see the warning. You can read more about this at www.diamond-cut.com.au if you want.

We have considered making more of this and other types of information available to online shoppers for a small monthly subscription, but we never get time to do all these things.

Do y'all think we should do it?

 

[Rook]

Gary,

Are you saying that there is a chance this diamond will chip due to the thin to medium girdle? Or due to the thin to medium girdle combined with the thin crown? i.e. will a diamond with a say 14-15% crown and a thin to medium girdle have the same potential to chip?

 

[Mara]

Thanks for the additional info, Garry. I expressed the concern on chipping to our jeweler and he said that we can design a setting to try to maximize protection to the stone, and that also the fact that we are using platinum will be of some help as well. Also as you suggested, he said that we can get a type of insurance to help protect against chippage.

We went with this stone for a few reasons..my boyfriend was never 100% sold on purchasing online..but he would have if I had come up with a spectacular deal. Which I did, but then we decided to contact this jeweler to see if he could match, which he did. That is why the prices are all the same, we were considering the online diamond very seriously and Jeff matched the price no matter what he brought in, to try to get our business..which we very much appreciate.

Of the two stones he brought in, we all loved the larger diameter one best, but for the slight darkness inside the table, which was obviously more visible to me than anyone else! I also don't have BIG HAIR, but I was definitely bringing up the stone close to my eye to look at it more often than keeping it at a faraway angle. The spread was a factor, as the other same-size diamond looked much smaller, and also we loved the fact that the larger diam stone was a VS1 and extremely clean. I was trying to convince myself that I could get an SI1, but when I saw the one he had brought in, my hawk-eye caught a carbon inclusion right off. No one else could see it without the 10x loupe. It could have been set under a prong, but I love a clean diamond, and the VS1 was so incredibly clean. Everyone thought that the larger diam one sparkled just as nicely as the one that fit inside of a Tolkowsky Ideal Cut range (and this one got a 1 on the HCA), and when we left..unbenownst to me, my boyfriend had already 85% of the way made up his mind for the larger diam one.

However, he knew I'd done all this research and he wanted to see what the forum AND the HCA said. While we got a few warnings, he didn't see anything super worrying (e.g. oh no-- that stone will disintegrate in 5 years due to its extremely shallow crown), and even saw a few things that were very interesting (e.g. leonid's diamond calculator images that showed excellent light return and virtually no light leakage for a perfectly symmetrical stone), so that pretty much made up his mind. Especially when I began exhibiting symptoms of quiet hysteria (okay not quite but close) on not being able to make the decision.

So he made the call (literally) and got the diamond. Jeff knows our concerns and he still maintains that this stone is the better deal. Since my girlfriend whose family has worked with him for 20 years buys WAY more diamonds a year than I ever will, I have to trust that he'll do us right. So we are now the proud owners of a large spread diamond, sitting in a safe in Northern California along the coast..waiting for us to design the setting. We also know we can trade in/up later so if we are not massively in love with the stone and final ring, we can work on that later. But I'm really not worried.

Thanks to everyone for their help on this extremely long and intensive post (and process!). I appreciate the posts, pictures and the printouts from the HCA and the Diamond Calculator. Last nite I was a little concerned wondering if we had made the right decision, and then I thought, I could find something wrong with probably any diamond, and there are thousands of diamonds in the world to choose from. My boyfriend pointed out that if I wanted to be so anal we could 'look forever' for the right thing or just make an educated decision.

In the end--he told me he loved this diamond right off the bat, because of the darker center and more sparkle around the edges, he says it reminds him of me and my personality..so if we didn't get a technically perfect diamond, we did get one with character. Which I can definitely appreciate!

 

[pricescope]

Mara, Congatulations and enjoy your diamond!