Repost from "Show-me": I''m new & need some input

[GEMGAL123]

Hi everyone! I''m new here and just have a couple of questions that you may be able to answer. I am engaged and LOVE my ring, however, it wasn''t until after the fact that I learned a few things I didn''t know before. I was pretty educated as far as the 4 c''s, BUT what I didn''t know (sorry if this sounds stupid) was that just because you have the same carat weight as someone, your ring could look larger or smaller depending on what shape it was. For example, I have a round and it doesn''t look as large as someone I know who has a different "fancy" shape & I actually have a larger carat weight! I was so suprised when I saw this. I mean we''re talking about a pretty significant difference in size. Has anyone noticed this with their round stones in comparison to others?
Thanks to all!

 

[verticalhorizon]

Absolutely. This is one of the things retailers sometimes don't tell you right off the bat, esp. if they're trying to get rid of some inventory.

You can even have a discrepancy in sizes among the same cut style (like Round Brilliant) in the same carat weight!

If a diamond is cut too deep it will appear smaller... cut too shallow, wider... and if the girdle is too thick, smaller. This is why it's important to find out the dimensions in mm, in addition to the carat weight... because carats only tell you weight.

The other numbers, let you weed out possible stones that will perform poorly. However, you can never really be sure until you seem them up front.

B/c you have a round, your stone may appear smaller, but perhaps it's more brilliant or a better color than the fancy in question. For some people, quality is preferred over quantity.

Please note that shallow stones aren't better for their weight, necessarily, b/c they won't reflect light the same way a well balanced cut diamond will, even though it will appear bigger than its weight.

 

[hoorray]

Well said VH...

What a lot of people miss in the 4 c's is that carat is a weight, not a size dimension. Different cuts have the weight in different places, and as VH says, the same cuts may have different sized stones for the same carat weight. Ex a well cut 1ct round stone should be about 6.5 mm. Many pooly cut stones are smaller than this and some are larger if they are shallow.

 

[GEMGAL123]

wow, very interesting -thank you for the information. Mine is a 1.5 carat round brilliant. It is really a beautiful stone - it's not such a concern for me. BUT when I saw another stone that has the same carat weight, I couldn't believe it!! What is considered a "good" depth for the ring to be? Anyone know what is considered appropriate for a 1.5 round? (ex as someone said, a 1ct would be the eraser of a pencil, or a hole punch etc...)

Thank you again

 

[valeria101]

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On 5/18/2004 4:44:48 PM GEMGAL123 wrote:



Anyone know what is considered appropriate for a 1.5 round? (ex as someone said, a 1ct would be the eraser of a pencil, or a hole punch etc...)

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The diameter of a 1.5 cts round would get about 7.5mm - a bit more than the average pen.

The preffered depth of the cut varies with the shape of the stone (making for a complicated debate). For rounds, the "ideal cut" parameters specify approx. 59%-63% depth, with most stones hovering around 60%. For the others? Well... you might want to inspect a certain set of tables on gemappraisers.com (or the Fancy Cuts tutorial here - same link but more organized introduction) to see what is acceptable and what is preffered - but there is no definition of "ideal" cut parameters for non-rounds (and no general agreement for rounds, for that matter). However, in any case, a stone would definitely not get the badge for being a fine cut for it's depth alone - sure that.

You do not specify what shape was that that looked so much larger - some would say that elongated shapes look large or their weigt (marquize, pear... thin rectangular cuts) since the longer side compares favorably with either the size of the finger or the width of the ring's band or what not. Also, I didn't realize people had such different ring sized until I hit PS! Stones definitely look larger on small hands, for what's that worth.

 

[verticalhorizon]

I dunno... an ideal cut 1.5ct Rb should be what?... mot quite 7.5mm across? Someone else will have to confirm this.

The exact size is less of an issue (as long as it's close), but for maximum performance, here are the specs for AGS ideal.