Do Small Differences in Angles Make A Difference?

[melis6886]

Hi Everyone,

I was wondering if you could give me guidance on which of these 2 diamonds you prefer given that color, clarity, and size are all the same. So base on the specs/angles of the diamonds, which would have more sparkle? I’m requesting an ASET image for the GIA diamond but for comparison sake, if I only had these angles to go by, which would you advise? Would having a pavilion angle that’s a bit shallower (40.6) be ok for this crown angle (34.5)? What kind of “personality” would you say each of these diamond would exhibit giving their specs? I think I may be splitting hairs here but since it’s a big purchase I thought I’d check with the experts here . Thanks so much for your help!


Diamond 1 --- Diamond 2
Cert --- GIA ---- AGS
Table -- 57% --- 55.4%
Depth - 61.2% - 61.8%
Crown -- 34.5 --- 34.5
Pavilion - 40.6 --- 40.7
LGF --- 80% ---- 76%
Star --- 50% ---- 50%
Culet --- none ---- pointed

 

[Roqsteady]

Keep in mind GIA rounds their crown angles to the nears 0.5 degrees, so that 34.5 could be anywhere from a 34.25 to a 34.74. Pavillion angles with the GIA are rounded to the nearest 0.2 degrees, so it goes 40.4, 40.6, 40.8, etc. Regardless though, both of these diamonds have crown and pavillion angles in the middle of the AGS ideal range (the sweet spot), so they are both likely to exhibit good brilliance as well as fire (but confirming with an idealscope/ASET is still best advised). And you probably wouldn't be able to tell the difference.

The one difference in "personality" I can tell is possibly from the LGFs. Granted, again GIA rounds the LGFs to the nearest 5 percent, so an 80% could mean 78 or 82, but regardless it is definitely longer than a 76. Longer LGFs (around 80) tend to result in skinnier arrows and throw off more splintery flashes of light, while shorter arrows (LGFs around 75) will tend to show broader chunkier flashes of light. You will also see this in the hearts pattern where longer LGFs result in clefting of the hearts (LGFs past 78 or so). Neither is necessary better than the other, but I think in general most people don't stray too far from 75-80.

 

[John P]

Most of the numbers are averages of 8-16 measurements. They're promising, but ideal-scope or ASET will reveal more about consistency. If the AGS has 0 performance that's also a great indicator.

 

[diamondseeker2006]

Don't choose based on numbers. Get idealscope images on both of them and then come back and we can help you.