Measurment versus carat question

[katamari]

Should it raise any concern that two diamonds with the same carat weight have seemingly different measurements? Also, what would constitute a ''big'' difference (given how small a mm is)?

I have been looking at diamonds in the 1/2 - 3/4 carat range for my e-ring. Right now, I am looking at two .72 asschers, one measures 4.86*4.86*3.22 and the other is 5.11*5.13*3.41. Is this a problem if they are similar on other specs? Why the difference?

Thanks!

 

[dockman3]

I"m pretty sure you got something wrong there. I don''t think two stones can be the same ct weight and yet every dimension of one stone is bigger than the other. I would expect the one with larger length and width to be shallower than the smaller one. This is quite common, but there''s no way that your two stones are the same ct weight with those dimensions. I guess I might be missing something because I don''t know much about Asschers, but from a mathematical point of view, you can''t have two different volumes of the same material weight the same amount.

 

[katamari]

That''s what I am thinking, too. I guess my inclination was to think that there is something wrong with one of the diamonds. But, it is also possible there is a typo on the website or something. Guess I should check with JA.

 

[dockman3]

Yeah, double check the site or have them double check the certs because there''s a typo somewhere. I''m sure JA would be more than happy to help you out in this case.

 

[purrfectpear]

Dockman is mostly correct. You actually can have two same carat stones with slightly different dimensions due to girdle thickness variances. I don''t think a thin/thick girdle could make up that much difference though?

 

[lisamarie]

If you look at the profile of an asscher, the sides don't form two straight lines like they do on a round - it's a bit curved. Maybe the asscher with the smaller dimensions is more bottom-heavy? Or maybe the asscher with the larger dimensions is more octagonal so the larger cut corners = less weight?

 

[JulieN]

I think it can happen if the pavilion bulges more on the smaller-dimensioned stone.

 

[strmrdr]

Date: 6/25/2008 8:08:38 PM
Author: lisamarie
If you look at the profile of an asscher, the sides don't form two straight lines like they do on a round - it's a bit curved. Maybe the asscher with the smaller dimensions is more bottom-heavy? Or maybe the asscher with the larger dimensions is more octagonal so the larger cut corners = less weight?

correct, table size is another variable as is crown angles and height.
With step cuts you can have 2 diamonds the same LxWxH measurements and even table% and weight that look nothing like each other from the top and from the sides.

 

[katamari]

Very helpful, everyone. I definitely over-analyze everything, and this is certainly a purchase I want to do right. So, I really appreciate it!

I have been debating about bringing in diamonds to look at and/or buying one unset and then sending it in for the setting, because I have felt that, with out budget, it may be overkill. But, through everyone''s help, I do think it will be the only way I can be completely satisfied.

 

[diamondfan]

I think carat weight is deceiving. Just like two 5 foot tall 100 pound women can be shaped differently, two diamonds of the same carat weight can be different. Another way to look at it is you can take 50 people all who weigh 100 pounds and they will not all look the same, if that makes sense...due to other variables!

 

[katamari]

Great point, diamondfan.



And I thought picking out my e-ring was going to be easy. . . It has been fun, though

 

[Lorelei]

This might be helpful - http://diamonds.pricescope.com/spread.asp