Which one is better quality?

[macchio123]

Which diamond is a bette value and quality? any thoughts are greatly appreciated. I really liked the 1.68 ct but wanted an EX cut. I like the 1.52 ct but wanted a whiter color.

1.68ct
Round
color E
clarity SI2
VG-Cut
GIA
62.5 59 ST-TK/F N VG VG N 7.52 - 7.58 x 4.72 mm

OR

1.52ct
Round
color H
clarity VS2
EX-Cut
GIA
62.8 54 MD-ST/F N EX EX N 7.30 - 7.36 x 4.60 mm

 

[stone-cold11]

What are the crown and pavilion angles?

 

[Lorelei]

Date: 4/18/2010 12:10:04 AM
Author: Stone-cold11
What are the crown and pavilion angles?

Ditto, they are both rather deep but the angles will tell us more.

 

[macchio123]

We didn''t get that information in the quote from the jeweler. What would be good crown and paviliion angles? We''ll be seeing the jeweler this weekend.

 

[stone-cold11]

ask for the GIA report number.

Play with the cut adviser to get an understanding of what crown angle works with what pavilion angle for a given table.
https://www.pricescope.com/cutadviser.asp

 

[Lorelei]

Date: 4/19/2010 12:35:18 PM
Author: macchio123
We didn't get that information in the quote from the jeweler. What would be good crown and paviliion angles? We'll be seeing the jeweler this weekend.

If you want to narrow the field to get a well cut stone, use the values below as a guide, however if you find a diamond you love that doesn't quite fit the suggested ranges then thats fine. With pavilion angles you have less flexibility than with crown angles so I would suggest keeping pavilion angles between 40.6 - 41 degrees to be safe as even with a good HCA score if the crown angle appears to balance, you can get undesirable issues such as leakage or colour entrapment from steep pavilion angles in some cases.

depth - 60 - 62% - although my personal preference is to allow up to 62.4%
table - 54- 57% - if you like the larger tabled look then you can go up to around 60% or a little higher, suggest a max of 61%
crown angle - 34- 35 degrees
pavilion angle - 40.6- 41 degrees
girdle - avoid extremes, look for thin to slightly thick, thin to medium etc
polish and symmetry - very good and above


note - with crown and pavilion angles at the shallower ends ( CA 34- PA 40.6) and steeper ( CA 35- PA 41) check to make sure these angles complement in that particular diamond - eyeballs, Idealscope, trusted vendor input - check as appropriate!

As the above implies, configurations depend on each other. A little give here can still work with a little take there.

From expert John Pollard.

With that said, here's a "Cliff's Notes" for staying near Tolkowsky/ideal angles with reports (their numbers are rounded): A crown angle of 34.0, 34.5 or 35.0 is usually safe with a 40.8 pavilion angle. If pavilion angle = 40.6 lean toward a 34.5-35.0 crown. If pavilion angle = 41 lean toward a 34.0-34.5 crown.

GIA "EX" in cut is great at its heart, but it ranges a bit wider than some people prefer, particularly in deep combinations (pavilion > 41 with crown > 35).