Jump to content

Radiant Diamond


Recommended Posts

I am now looking for a radiant diamond for an engagement ring. I am somewhat confused about what depth/table percentages I should be focusing on when searching for this diamond. I found the following website that lists the preferred depth and table percentages:




One of the jewelers I have been talking to, gave me some preferred table and depth percentages for radiant diamonds, and they differ considerably from the numbers given by the above website.


Premium Ideal:

Total Depth %: 63-70

Table %: 68-72



Total Depth %: 63-70

Table %: 68-72



Total Depth %: 63-72

Table %: 67-74


Very Good:

Total Depth %: 62-74

Table %: 65-78



Total Depth %: 56-78

Table %: 63-80



Total Depth %: 55-83

Table %: 53-83


Which of these specifications should I use? The internet's or the jeweler's? I read an old post on this forum (2005) that stated that depth and table are somewhat useless when searching for a radiant diamond.


A different jeweler I am using found a radiant diamond with the following specs:


1.53 carats

Color: F

Clarity: VS2

6.39 x 6.25

No fluorescence

Polish: very good

Symmetry: good

Depth: 76%

Table: 75%

Cost: $10,500


Based on just the table and depth, these dimensions are out of range for an ideal-excellent for both standards. Based on the internet dimensions, both table and depth rate as "fair" while based on the jeweler's dimensions, the depth is rated "good" while the table is "very good". Should I tell the jeweler to request the diamond from the diamond broker so that I can see it or based on these dimensions would I be wasting time by requesting to see it?


Your help is greatly appreciated.



Link to comment
Share on other sites

Fancy shape diamonds, of which the Radiant Cut is, can not be evaluated simply based on the Table and Depth percentages. This is because of their irregular architecture and the fact that even very slight alterations in their facet size, cut angle, and alignment can have a dramatic effect on the diamonds face up beauty and appearance.


The fact that these "number" charts from two different jewelers overlap clearly indicates that going by such "numbers" is worthless and may even be detrimental in your getting a top-flight diamond.


Two radiant Cut diamonds with the same exact specs can look dramatically different.


You need to keep an open mind and look at these stones in various lighting conditions to see which appeals to you the most.

Link to comment
Share on other sites

Hi all!


To me, the worst thing about these completely USELESS "Guides" is that they give shoppers the impression that dealers and cutters abide by these misleading stat tabvles.

They most certainly DO NOT.

There's no accurate rating system for a radiant cut diamond's cut. No GIA "Cut Grade"



It's true that extremely deep stones will look smal- but even that is not a blanket statment- a 75% depth diamond of 2.00carats might look like a 1.75 of 65% depth.

BUT- it's entirely possible someone might like the look of the deeper stone better.

And if the price takes the depth into account- and the stone is well priced- it might be the best choice.




Here's one of ours- and it's stats....

ITEM #: R2185

Radiant Cut Diamond, Loose


WEIGHT: 1.51ct

SHAPE: Radiant Cut



MEASUREMENTS: 6.52 x 6.29 x 4.30 mm






GIA REPORT #: 15802595

Link to comment
Share on other sites

I agree with the above, those charts are worse than useless because they lead people to believe thing that just aren't so. At best a lovely stone will come out 'ideal' but they are equally likely to call a fireball a stinker. What you're asking is NOT a reasonable way to buy diamonds. Talk to the dealer and ask them to look at the diamonds and provide you with a visual assessment of the cutting based on their expert opinion. If it passes that, arrange to look at it yourself. What you're doing is like buying a car based on the specific details of the paint color and then not taking it for a test drive. Sometimes it works out ok, but I wouldn't bet on it.



Link to comment
Share on other sites

  • 3 weeks later...

Thank you for everyone's input. I have another question regarding the radiant cut. What should the spec range be for the girdle so that I don't risk chipping the diamond but also so that I am not paying for carats that won't help the diamond shine?


Thanks again,



Link to comment
Share on other sites

I would avoid 'extremely thin' and 'extremely thick'. 'Very thin' deserves a second look to see the details.


It varies a bit from lab to lab both in language and the way they measure things but in most case the scale looks something like this:


extremely thin

very thin



slightly thick


very thick

extremely thick



Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...