real/synthetic diamond checking device?

[kevin_79]

I went to a local B&M store last weekend. While I was looking round, I heard another customer in the store asked the jeweler if the diamond is real. After about 30 seconds of silence, I heard a long beeeeeeeep sound and the jeweler said "it is real".

I left right after that so I didn''t have a chance to ask the jeweler about the device that she used to check out the diamond. Is there any equipments/devices can do that or it was just a scam performed by a jeweler?

 

[Richard Sherwood]

There are two electronic testers on the market. One which will tell if a stone is cubic zirconia, and the other which will tell if a stone is cubic zirconia or moissanite, another diamond imitation.

The tester which catches only cz''s will miss the moissanites, testing positive for them as if diamond, so it is pretty much outmoded. The other one is a handy instrument for non-gemologist jewelers to have. Most gemologists eschew both, trusting their eyes and a scope over the machines, which can malfunction or give errant readings in a minority of cases.

 

[Rhino]

Hi Kevin,

It''s a thermal conductivity tester. Diamonds generate a certain amount of heat which is detectable by these devices.

 

[Rhino]

So true Rich. With moisannite I just stick em under the microscope and look for the double reflection at the facet junctions.

 

[RockDoc]

RE: Testing probes....

Certainly a useful back up.. but education is the key here. Diamond and CZ are very easily separated, without the use of probes, which on diamond coated cz''s I understand can''t be depended upon.

I wrote about this on DT long time ago. But I''ll repeat the test procedure here.

There are several "requirements".

1. the stone being examined must be very clean.

2. you need a bright light which you can position over one of your shoulders.

3. You can do this with mounted stones, but if the mounting blocks refraction/reflection you need to "weigh" the image you consider with your eye.

It helps to have a cz and a diamond so you can study the differences, so you can recognize the minute visible characteristics. But it isn''t difficult to master once you have a little practice.


Most people probably have dominant vision in their right eye, so position yourself so that the bright light ( the more like a spotlight is better than a regular incandescent bulb.

Take the stone you want to "test" and move it extremely close to the eyeball... as close as you can get it. Move so the light is in the position that illuminates the stone the most.

Look into the stone and notice the spectral colors, sort of like a rainbow. See if the colors are connected to each other. This looks like a sort of broad color band with all the colors of the rainbow. This is a visible spectrum.... and in a diamond it will appear like this.

Then look at the CZ. You''ll notice the spectral colors are separated and "go" in different directions. This is how a CZ appears.

The key here is to be able to see the very small spectral colors, that only getting the stone almost on the eyeball requires. Of course be very careful not to actually touch the eye.

Now I haven''t seen a CZ that is diamond coated, but that could be an exception.

If any of you are "brave" enough to try this, I''d be interested in hearing your observations..

Rockdoc

 

[RockDoc]

IMPORTANT NOTE:


A SYNTHETIC DIAMOND has the same properties as a natural diamond. The difference is that it is man made.

A CZ / Moissannite etc, is an IMITATION DIAMOND.. Also referred to as a simulant/simulated .

The probes can separate imitation from genuine diamond, but a synthetic may test the same way as diamond does.



Rockdoc

 

[RockDoc]

For use with probes..

The diamond must be "squeaky" clean. or a real diamond may test as a "phony".

Rockdoc

 

[Rhino]

Good input RockHound

 

[RockDoc]

Date: 3/31/2005 8:38

5 PM
Author: Rhino
Good input RockHound

Rhino

So now I'm a hound instead of a doc??....hmmmm woof, woof?

Have you tried the test I described? Curious to hear if you think it is obviously visible to you.

You have any of them diamond coated CZ critters?

Rock Woof! ( I'm more dangerous this way, don't want to give me bitin' teeth.... sure you remember my nickname on Poly ( Fang )....

( I joke with Rhino all the time, he knows that but some readers might not know that ).....

 

[kevin_79]

thanks to all the experts for providing the knowledge

 

[JohnQuixote]

Good discussion.