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 Post subject: Grading common sized melee in appraisal
PostPosted: Fri Mar 31, 2023 1:40 pm 
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Hello everybody! I tend to go over my manuals when things slow down to keep my skills sharp and in searching haven't been unable to come up with the answer to a very basic question:
Lets say i'm measuring melee in a cluster ring that has stones that aren't precisely the same size. How much variance can there be between stones before i must individually document each stone instead of grouping them and using the average size?
Thank you in advance!


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 Post subject: Re: Grading common sized melee in appraisal
PostPosted: Fri Mar 31, 2023 3:34 pm 
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This is what I would do.
The sapphire is surrounded by 30 full cut diamonds, varying in size from 1.5 to 1.75mm, for an approximate total weight of 0.52 carat.

The Deco brooch is diamond-set.
Diamond Description
Quantity: 120 total
Measurements: 25: 2.4mm.....1.25 cttw
13: 3.0mm.....1.30cttw
46: 2.0mm......1.08cttw
36: 1.25mm....0.36cttw

Total diamond weight:4.71 cttw (calculated approximation)


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 Post subject: Re: Grading common sized melee in appraisal
PostPosted: Mon Apr 03, 2023 4:43 pm 
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Barbra Voltaire, FGG wrote:
This is what I would do.
The sapphire is surrounded by 30 full cut diamonds, varying in size from 1.5 to 1.75mm, for an approximate total weight of 0.52 carat.

The Deco brooch is diamond-set.
Diamond Description
Quantity: 120 total
Measurements: 25: 2.4mm
13: 3.0mm

A wonderful explanation. An emphatic thank you goes to you Barbra!


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 Post subject: Re: Grading common sized melee in appraisal
PostPosted: Mon Apr 03, 2023 5:22 pm 
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Shoot. That got posted before I completed the post.
Look now. It should make more sense.


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 Post subject: Re: Grading common sized melee in appraisal
PostPosted: Thu Apr 06, 2023 2:25 pm 
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For myself I usually go by the small variances that might be found in diamond packages. So for example if you have a diamond that is supposed to be 2.0 mm you'll probably get diamonds in the 1.9 - 2.1 mm range in most cases. I've usually found they put a 0.2mm variance for most packages of stones so I use that as a rough guide for myself.

A recent one I had of course pushed that to the limit a little as they had graduating diamonds in a ring ranging from 0.8 mm to 3.4 mm but thankfully it wasn't every 0.2mm that it went up in graduated sizes.

Just my 2 cents on the subject anyway. As long as it's accurately labelled and the estimated weight is as accurate as you can get then up here in Canada they don't have any rules on what the variance allowed should be.

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 Post subject: Re: Grading common sized melee in appraisal
PostPosted: Thu Apr 06, 2023 10:34 pm 
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I measure and report the actual mm of all stones in a mounting.


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