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 Post subject: half moon cut brilliant
PostPosted: Wed Aug 25, 2021 12:53 am 
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Joined: Tue Nov 04, 2008 11:59 pm
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Hi all,

I am trying to see any data on half-moon cut diamonds and their near-ideal proportions. Looking to get a matching pair as side stones for a ring and I am looking at GIA reports with variable % as to symmetry. Is there a guideline on what is the acceptable proportion for Half Moon cut brilliant stones? I know the length to width ratio should be at an acceptable level but not sure the numbers for this does anyone a chart comparison or can u let me know what the max table %, total depth L: W I should be looking at and to avoid bow ties ofcourse.

Thank you for any info provided.

Cheers!

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 Post subject: Re: half moon cut brilliant
PostPosted: Wed Aug 25, 2021 1:21 am 
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Location: San Marcos, CA
Have you checked the Gia website, sounds like something they would detail or call the library here in Carlsbad, California. I am not positive but I believe they are considered fancy cut. I found this on the Gia https://www.gia.edu/gia-faq-analysis-grading-system-fancy-shape-diamond

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 Post subject: Re: half moon cut brilliant
PostPosted: Wed Aug 25, 2021 5:40 am 
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You will not find a simple list of numbers to examine in determining the cut quality of a fancy shape. It is mostly about attractiveness and personal preferences when considering the outline of the stone, and the reflection pattern. Other things like symmetry, polish are more objective and judged in the same way as RBC diamonds.

The Half Moon is really just 1/2 of a round. It is a shape not a cut. It could be cut in an variety of facet patterns from Brilliant to Step Cut.

You will want to look at the stone from the top, and estimate the size of any aberrations like Bow Ties. You will also want to look at bulge factor to see if the stone is carrying excess weight. If the stone has an attractive pattern without such things give it a high score.

If you are choosing a Brilliant cut 1/2 round it seems to me that the best performance will come from a stone that follows the angles, facet pattern, and proportions of a Standard RBC Diamond on the round side , and a Barion style of the Crescent side.

In the end, pick a pair you like the way they look best with the stone they will be accenting.


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 Post subject: Re: half moon cut brilliant
PostPosted: Wed Aug 25, 2021 1:09 pm 
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Ditto. :smt023


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 Post subject: Re: half moon cut brilliant
PostPosted: Sun Aug 29, 2021 9:46 pm 
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Joined: Tue Nov 04, 2008 11:59 pm
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Thank you glhays and 1bwana1 much appreciated for the info.

Cheers!

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