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diannec18

Shiny_Rock
Joined
Mar 14, 2015
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128
OK guys, I'm back and after two weeks of non stop researching, I'm not as much of a newbie. I've started a new thread, as tagging onto the end of my old one wasn't very fruitful. So anyway, the SO has given me permission to find a stone of my liking, and then he'll handle getting it set. I've decided that I want at least a .55, and I want tons of fire. Don't want it to look yellow and I want it eye clean.

In terms of vendors, I feel most comfortable with James Allen or ritani, because of their options for viewing the stones. We don't have enough disposable income or time to deal with shipping stones back and forth just so we can see what they look like in real life.

Theoretically, I think I'd like to order something 4-5 days from now, as were looking at probably a couple months before SO would have a ring in hand.

I've been running every stone I've looked at through the HCA, but now I'm pretty confused as to how much I should rely on those figures because of something a poster on a previous thread said. How much should i rely on the HCA?

Here's a list of the stones I'm most interested in on James Allen

http://www.jamesallen.com/loose-diamonds/round-cut/0.70-carat-j-color-vs2-clarity-very-good-cut-sku-453854

http://www.jamesallen.com/loose-diamonds/round-cut/0.60-carat-i-color-vs2-clarity-excellent-cut-sku-430369

http://www.jamesallen.com/loose-diamonds/round-cut/0.60-carat-h-color-si2-clarity-excellent-cut-sku-479437

http://www.jamesallen.com/loose-diamonds/round-cut/0.55-carat-g-color-si1-clarity-excellent-cut-sku-454789

http://www.jamesallen.com/loose-diamonds/round-cut/0.64-carat-j-color-vvs2-clarity-excellent-cut-sku-458457

http://www.jamesallen.com/loose-diamonds/round-cut/0.60-carat-i-color-vvs2-clarity-very-good-cut-sku-443358

http://www.jamesallen.com/loose-diamonds/round-cut/0.63-carat-i-color-vs2-clarity-very-good-cut-sku-454559


- My thoughts were that the HCA rating is a better scale than gia cut grade, and so I was considering some very good cuts if they have excellent HCA ratings. Should I not be doing that?


Also, a service rep at James Allen recommended this stone
http://www.jamesallen.com/loose-diamonds/round-cut/0.60-carat-h-color-si2-clarity-excellent-cut-sku-479437

because she said it would be a much better stone than:
http://www.jamesallen.com/loose-diamonds/round-cut/0.60-carat-i-color-vs2-clarity-excellent-cut-sku-430369

According the the HCA, its not at all a better stone, and I told her it looks cloudy, but she said it will be very sparkly, more so than the one below. Is she correct, or is this an indication to completely ignore the suggestions by their customer service?
 
If it is fire you are after I think the second one Kobi posted looks great. I'd keep it on your short list and try to pick out 2 more that you like, then get them on hold while you request idealscope images.
 
Yes, I like that second one as well. Thanks kobi

Can anyone explain to me why this stone is more likely to produce fire over the ones I've chosen? I'd really like to understand how to recognize a good stone
 
It all has to do with Holloway theories. Within the range of ideal Holloway diamonds (HCA below 2.0) there's a tradeoff between fire and brilliance (light return).

Fiery Ideal Cut, which maximizes fire, will have a crown angle of 35 degrees or higher.

Brilliant Ideal Cut, which maximizes light return or brilliance, will have a crown angle of 32 degrees or less.

A compromise position, the Tolkowsky Ideal Cut will have a crown angle between 32.5 and 35.5.

One of your picks probably has the most fire of any of the diamonds chosen by anybody:

http://www.jamesallen.com/loose-diamonds/round-cut/0.70-carat-j-color-vs2-clarity-very-good-cut-sku-453854

The 38 degree crown angle, the slightly smaller table, and the higher depth percentage leads to all those amazing fiery flashes. But it loses something in brilliance or light return. Still it has an HCA of 1.2 so you're still in the right range.

http://www.jamesallen.com/loose-diamonds/round-cut/0.60-carat-i-color-vs2-clarity-excellent-cut-sku-453281

This diamond recommended by the other two posters has an HCA of 0.9 but also a 35 degree crown angle, so it also tends towards slightly more fire than light return.
 
And also, to help start narrowing down, which diamonds should I definitely remove off that large list I posted? Or should I trash them all?
 
Do you care if the diamond has inclusions or blemishes that are visible to the naked eye?
 
Hi Pfunk and Daniel
Thanks for your help. Fire is definitely number one for me (I love rainbows!!!), but when you say I'd be losing in brilliance or light return, what does that mean exactly?

I've decided that I'm okay if the stone is not 100% eye clean, but I would only want one tiny visible imperfection, and definitely not something that is right in the middle of the stone. Some posters on another forum I belong to pointed out that the benefit of a visible inclusion is it allows you to always identify your stone (eliminating the dreadful stone switch that is rumored to occur).
 
Brilliance and fire are different qualities. And there can be a tradeoff between those qualities even with sub HCA 2.0 diamonds.

https://www.pricescope.com/wiki/diamonds/diamond-brilliance-fire-scintillation

For example: Wellcut OEC diamonds have tremendous fire, or flashes of rainbow color, much more than the typical modern round brilliant, which are cut for brilliance and light return.

The MRB will be brighter than the OEC in most conditions, but the OEC will have more rainbows.

So within MRB ideal cuts, there are some diamonds with more rainbow flashes and slightly less brilliance. And vice versa. And the best thing to do may be to try to find the best balance of those qualities (and scintillation etc).
 
So its a bad idea to sacrifice on brilliance in favor of fire?

I've been doing some youtube research, and I'm wondering, will the deeply cut J (the .7) have light leakage?
 
Theoretically the excellent HCA score should temper concerns about light leakage. But that will have to be confirmed with Idealscope images, or having a jeweler bringing in a couple of your choice diamonds and making a side-by-side video for comparison (doesn't Good Old Gold do this?).

You might start thinking about how you might get an inperson look at your preferred choices.
 
no in person option with james allen other than purchase. but I still feel more comfortable with them versus spots that will do virtual gemologist appts because i wouldnt even know where to start when only having stats to look at...
 
Bump
 
You probably already know this, but you can request idealscope images for up to 3 diamonds from JamesAllen at no charge. Once you narrow down to 3, it should help you confirm light return and any leakage.
 
faytastic|1427906328|3855474 said:
You probably already know this, but you can request idealscope images for up to 3 diamonds from JamesAllen at no charge. Once you narrow down to 3, it should help you confirm light return and any leakage.

Yes Faytastic, I actually just did that a couple hours ago. I was having a really hard time narrowing down to three though. They told me it would take about a week to get the images back, but I'm hoping theyre being conservative. Any idea how long it takes to get the idealscope images?
 
Many of their stones are with cutters in other parts of the world, so that is why there is a delay.

I saw this stone and wanted to tell you what is bad about it.

http://www.jamesallen.com/loose-diamonds/round-cut/0.70-carat-j-color-vs2-clarity-very-good-cut-sku-453854

It has a thick girdle which means it is hiding weight in the girdle which hurts the diameter. A well cut .70 should be around 5.7mm. Therefore, this diamond would have the appearance of a smaller stone.

It takes a lot of time to narrow down the GIA ex cut stones on JA. But I will tell you the parameters I use which help you get stones in the ideal cut range.

table: 54-58

depth: 60-62.3

crown angle: 34-35.0

pav angle: 40.6-41.0
 
A PS member is selling a 0.60 carat G SI, AGS 000 diamond (and setting) in the Pre-Loved PS Jewels section. In terms of cut you can't get better than that.
 
danielxlin|1427919080|3855520 said:
A PS member is selling a 0.60 carat G SI, AGS 000 diamond (and setting) in the Pre-Loved PS Jewels section. In terms of cut you can't get better than that.

This is an excellent suggestion although I am not sure if they will sell the stone separately from the setting.

[URL='https://www.pricescope.com/forum/preloved-ps-jewels/whiteflash-0-6-carat-round-diamond-ring-size-6-t211861.html']https://www.pricescope.com/forum/preloved-ps-jewels/whiteflash-0-6-carat-round-diamond-ring-size-6-t211861.html[/URL]
 
Definitely need the return policy and assurances that come with dealing with a reputable business, but thanks for the suggestion (and that's more than a little out of my budget ;)
 
cherryiice|1427808424|3854995 said:
Yes, I like that second one as well. Thanks kobi

Can anyone explain to me why this stone is more likely to produce fire over the ones I've chosen? I'd really like to understand how to recognize a good stone

No worries.

My personal taste is also for more of a firey stone. I like the combination of a smaller table and 35CA, and also find that the thicker lower halves 75% tend to throw off broader flashes of colour/light. I would happily purchase the one I posted for myself. Also, comparing it to others on JA, it appears to be a very good I colour (not much tint).. but how much of that is the actual stone or variations in photograph conditions could be up for debate.

Look forward to seeing your IS images.
 
I agree with Kobi's comments about the .60, I VS2. Everything looks great and hopefully the idealscope image will be, too!

Just for the record, I have had stones with anywhere from 34.5-35 crown angles and I really cannot detect any difference in fire. In reality, unless you spend a lot of time outside in the sun looking at your ring, you won't see fire very often! I always worry about people expecting fireworks or something! But I think those measurements are very nice and I also like the 75 LGF's!
 
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