Proportions on a Radiant cut?

[jls944]

Can anyone give me an idea of how to judge a radiant cut diamond? Are there guidelines to go by on the proportions or is it basically whatever looks good? I was looking at the HCA but I dont think that holds any guidance toward fancy cuts.

Thanks in advance.

 

[oldminer]

I have developed charts for cut grade parameters on www.gemappraisers.com that people often use as a guide. However, I want you to only use this sort of info as a screening tool, not as a way to make a final selection. Radiant cuts range from some of the most well cut and the worst cut diamonds. The variation is tremendous and one ought to physically examine a radiant diamond before buying it. Screening is useful. You don''t want an overly deep stone simply because it will look small for its carat weight and you generally pay by the carat. You don''t want a terrifically shallow stone, especially with a very thin girlde because shallow alone usually makes brilliancy diminish and combined with a very thin girdle the stone can become rather prone to chipping....

These things can be prevented by screening. Then you need to use your eyes.

 

[jls944]

I have been using your chart as a guide, but I was talking to a jeweler and he said that the depth % should be around 70 and the smaller the table the better. Is he correct to say this? I told him that he was way off because both table and depth should be in the range of 60-65. I think he was trying to pull a fast one on me.

 

[oldminer]

Everyone trys to sell what they have. It is difficult still to get regular depth radiant cuts when it is easy to get deepish ones that appear a good value for weight versus price. FInding a good one with a proper spread will not be easy.

 

[Garry H (Cut Nut)]

And becaus there are soooo many variables - cutters who are even trying their hardest to make the best radiants have little or no hope.

Our Cut Study group will solve this - but the solution will only be initially available for those manufacturers who we invite / elect to / work with us.

It took AGS a couple of years to work out Princess cuts - we will find a quicker better way for planning

 

[diamondsbylauren]

HI Everybody,
Dave''s post makes a lot of good points-
There are some really well cut radiants being cut today- even without Garry''s help...hehehe

Also true that many times people try and sell what they have.
I''ve seen some beautiful Radiant Cuts with 70% depth- but clearly, depths in the 60''s are preferable. Whoever said 70 is the preferred depth is showing they are not really up to speed on the cut.

Table size- small tables ( low 60''s) can look nice, and so can large tables- up in the mid 70''s. That''s one of the great things about the cut, many different combinations produce great results.

It''s true, there are some seriously ugly radiant cuts on the market, but there''s quite a few beauties out there too.

If you post specifics from GIA report it will be possible to make specualtive comments- a good digital photo will also help.
Ultimately you will be the expert- you can tell if something is beautiful to you better than anyone else.

 

[jls944]

Thanks for the info guys. That is very helpful!