New Mineral Named After GIA’s John Koivula
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 Post subject: Identifying Synthetic Diamond?
PostPosted: Fri Nov 03, 2006 6:35 am 
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Hi everyone,

I hope you guys can give me some insight on this.

A customer walked in this morning with a ring containing 100 tapered baguettes weighing approx. 2ct with a center diamond weighing approx. 4ct. The ring is set in an art deco style in 750 yellow gold.

She said that the ring belonged to her mother and it was a family heirloom. She's 80 years old by the way. Her mother had this in possession since the early 1950's. Anyway, this center 4ct diamond was a square Radiant Cut, with almost-perfect proportions. Since it's set in yellow gold, I'm guessing the colour is about J-K. Its clarity is IF, in my opinion. There are no certificates accompanying this item.

When I checked, the Radiant cut was only created in 1977.

So, what do you all think? I'm interested in purchasing it from her, but it's a bit odd, don't you think?

The question is, how do I identify it as synthetic or natural? There are no inclusions to tell from, and my SW/LW florescence lamp died on me. I feel very reluctant to let this one go.

I'll appreciate any comments on this. Thanks!

Ben


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PostPosted: Fri Nov 03, 2006 9:17 am 
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If the stone is actually from the 50's - it wouldn't be a "synthetic diamond" as GE wasn't putting out stones of that size or quality. The original synthetic stones in the 50's were not used for jewelry - they were mostly in the form of grit and were used for industrial purposes. GE did not announce the creation of the first cuttable, gem-quality synthetic diamond until 1970, the ones that were cut were only .26 ct - .46 ct in weight, and the highest clarity was VS.

I would take an RI on the stone as it could be a synthetic corundum. The "Internally Flawless" conclusion that you came to could easily explain synthetic corundum. Have you seen it under the microscope? Are you sure it's a Radiant cut and not a modified emerald cut, a step cut, or a mixed cut?

If you mean "imitation" - that is easy to determine with a thermal diamond tester that every jewelry store usually owns.

Could you post a picture of the ring?


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PostPosted: Fri Nov 03, 2006 11:19 am 
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Hi,

When in doubt, buy at the worst scenario.


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PostPosted: Sat Nov 04, 2006 1:06 am 
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I tested the diamond with a diamond tester that even separates diamond from moissanite. It showed that it was a diamond.

I'm positive it's a radiant cut. I am just in doubt regarding the person's story. Any way to test if it is a synthetic without the presence of inclusions or without using flourescence?


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PostPosted: Sat Nov 04, 2006 1:29 am 
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It is my understanding that it is difficult to produce synthetic colorless diamonds. Most of them are quite yellow.

I'm not sure a 4ct cololress synthetic faceted diamond exists, does it? You could easily find out by calling the GIA or Chatham Created Gems and asking them.


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PostPosted: Sat Nov 04, 2006 1:34 am 
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Barbra Voltaire wrote:
I'm not sure a 4ct cololress synthetic faceted diamond exists, does it?


I don't think it does either, Barbra.
If so, what is the likelyhood that this woman owns it? 8)


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 Post subject: Re: Identifying Synthetic Diamond?
PostPosted: Sat Nov 04, 2006 2:24 am 
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ben wrote:
When I checked, the Radiant cut was only created in 1977.

Hi Ben,
When you break the so-called "Radiant Cut" down what do you have? On its reports the GIA describes it as a ‘cut-cornered square mixed cut.’ Basically it's a cut-corner square with step-cut crown and brilliant-cut pavilion. Certainly that concept didn't just emerge from the wilderness in the 1970s. Someone somewhere had to be cutting in that style long before the name was copyrighted or trademarked.

Still this just doesn't pass the smell test for me. Rings with masses of baguettes around flashy centers became very popular in the 1980s. Adding the two together makes me wonder if the customer is telling you the whole truth. Is there a chance this could be stolen merchandise?

Rick Martin


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PostPosted: Sat Nov 04, 2006 4:46 am 
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Quote:
I'm not sure a 4ct cololress synthetic faceted diamond exists, does it?


I came across this article shortly before we had our guest chat with the gent from Apollo. It seems that yes, it does exist.


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PostPosted: Sat Nov 04, 2006 10:57 am 
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Thanks Nucky! I love this stuff!

The article (dated May 2005) doesn't say if these new synthetics have been made available to consumers yet. I'm sure the price is still very high to obtain one of these synthetic diamonds.

I still don't think ben's ring has a synthetic diamond in it, but would love to have the mystery solved.


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PostPosted: Sat Nov 04, 2006 11:04 am 
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I suspect that although Granny was at her prime in the 50's, this ring didn't exist until the '80's.


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PostPosted: Sat Nov 04, 2006 4:19 pm 
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If very lucky, you might find a diamond cut with a mix of brilliant and step facets with a clear dating from around 1930. Not all cut patters are classified and the unusual have a good chance to be very well executed or high quality because of the unusual skill involved and difference paid to finer diamonds. BUT, I have only seen two such stones, both in old British jewelry. I do not have pictures or anything, unfortunately. Just mentioned to relax the dating based on the release of the Radiant cut - there are exceptions to that.

The info of the seller could be flawed, but... that's allot of diamond and buying at worst scenario... what would that be? Moissanite price? Is it worth sending it to an independent lab? At least a few have high tech testing on board and may not be as expensive or backlogged as the major ones are.

Large synthetics exist, but I have never heard of any to have been sold at all - only that such samples have been produced as showpiece of the technologies responsible. Today, you could order one, but the offer of 'custom synethetics' is very recent (and still do not know if such large stones are really available).

My 2c :)


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PostPosted: Sun Nov 05, 2006 10:59 pm 
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Thanks for your input everyone. I just got a call this morning from the Granny. Our appointment is set for tomorrow to determine the price I am willing to pay her. She seems quite desperate to get rid of it. I wonder why?

Quote:
When you break the so-called "Radiant Cut" down what do you have? On its reports the GIA describes it as a ‘cut-cornered square mixed cut.’ Basically it's a cut-corner square with step-cut crown and brilliant-cut pavilion. Certainly that concept didn't just emerge from the wilderness in the 1970s. Someone somewhere had to be cutting in that style long before the name was copyrighted or trademarked.


I agree, it could have been created earlier than the 1970's. However, the proportions and symmetry was near excellent. Somehow, I don't think cutters in the 1970s or earlier could have achieved such precision in cutting.

Quote:
t is my understanding that it is difficult to produce synthetic colorless diamonds. Most of them are quite yellow.

I'm not sure a 4ct cololress synthetic faceted diamond exists, does it? You could easily find out by calling the GIA or Chatham Created Gems and asking them.


The center stone is actually a J-K colour, not colourless. I'll take a picture of it tomorrow and I will post it here. It's an absolute beaut!

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Benjamin W.
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PostPosted: Mon Nov 20, 2006 8:53 am 
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Hey everyone!
I finally bought the diamond...
It's actually bigger than I thought... it's approx. 5.62 cts.
Just to be sure, the weight estimation formula for radiant cuts is length x width x depth x 3.52 x 0.0026?

The measurements for this diamond is 9.38 x 9.26 x 7.08

Image


Got it at a really good price too!

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Benjamin W.
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