Important:  This is our old site *archive* and is no longer live (prices and inventory are outdated and not valid). 
Please visit directly to view our new site with live shopping.

  Infinite Menus, Copyright 2006, OpenCube Inc. All Rights Reserved.

DiamondNexus Labs - What is it?
Flawless man-made diamond, synthetic polycrystalline diamond or... plain CZ?

[Note: Full Disclosure:  We are a competitor to Diamond Nexus Labs.  We produce the Asha® Diamond Simulant which uses high-end, hand cut cz and a proprietary carbon amorphous diamond coating in its manufacture.]

For the past few years, we've seen some very interesting marketing techniques utilized by Diamond Nexus Labs in marketing their lab grown gemstone.  As a result of their changing claims and advertising about what their product is or is not, many people have been confused as to what the Diamond Nexus Labs gemstone is.  Is it really flawless man-made diamond as their ads state?  Is it a breakthrough polycrystalline compound as their website states?  Is it 'not CZ' as their customer service verbally states?

To try and find an answer, one might start by searching on Diamond Nexus Labs, resulting in an ad like this:

or this

Based on this, a reasonable person would assume their product is real lab grown diamonds.  

Interesting, because no lab in the world can currently produce white lab grown diamonds and sell them profitably.  Apollo diamond offers a few small ones from their R&D, but it's not a commercial production basis.  In addition, true lab grown diamonds are rarely 'flawless' or 'perfect' fact, they tend to have the same flaws and issues their mined counterparts have (we know a bit about real lab grown diamonds, having been the first to offer true lab grown diamonds on the web via our website).

Nevertheless, by visiting their site, we see that the terms have changed a bit - their header now advertises:

{Screenshot,, 11/15/2007}

So now we're unsure if they are offering diamond simulants or lab-grown diamonds.  

In their text on their homepage, they again switch back to talking about lab grown diamonds, stating 

"We invite you to learn more about lab-created diamonds in general and the Diamond Nexus Labs breakthrough.." 
{Homepage,, 11/15/2007}

which now implies their gemstones are a breakthrough product.  

To further add to the confusion, Diamond Nexus previously used to show product photos that were not photos of their product, but were in fact simply altered photos of natural diamonds (google image search was very revealing).  Here is one example from 2006: 

Original photo of a 1920's natural Asscher diamond by Nelson Rarities Photo as shown on Diamond Nexus website and saved Sept. 1, 2006.  This photo was used as the product photo for their Asscher cut.  
(blue arrows added after to highlight the leftover prongs). 

Seeking more information, we go into their 'news' center.  Here we encounter more confusion:

{Screenshot, DiamondNexusLabs, 12/06/07}

Now we see direct claims that the product they market is "almost perfect synthetic diamonds".  This article later mentions that their diamonds are polycrystalline, and there are numerous other articles in the news section talking about new "synthetic polycrystalline diamonds"...maybe the Diamond Nexus product is synthetic polycrystalline diamond?  

{Screenshot,, 11/15/2007}

However, gemologists do not agree that synthetic polycrystalline diamonds are glittering or brilliant.  In fact, this would be odd as polycrystalline means "many crystals" rather than one single crystal.  These are normally used for abrasives work and drilling, and do not make for gem quality stones as they are normally not transparent due to having so many crystals randomly oriented, which prevents light from readily flowing through.  The result is polycrystalline diamond of any size is dull and dark...which you can see by viewing a photo of actual synthetic polycrystalline diamond below: 

Photo of synthetic polycrystalline diamond pieces....not very gemlike. 
(Photo by Zhengzhou CutSky Industrial Co, Ltd).


Unclear as to why all the talk about polycrystalline diamonds, we continue reading and find this article: "Man-made diamonds: A Buyers Guide".  Here we are presented with a comparison of various materials used to created imitation diamonds, including some additional info on the Diamond Nexus product:

{Screenshot,, 11/15/2007}

and finally:

{Screenshot,, 11/15/2007}

Source link:


With that, we are told that:

  • Many simulant makers are selling CZ, but don't admit to it unless pressed (Diamond Nexus is happy to name them though), 

  • CZ is usually not good enough for fine jewelry.  

  • Diamond Nexus gemstones are the result of a fairly a new scientific advancement, only recently available in the US, 

  • Diamond Nexus gemstones are 'virtually identical to diamond' in hardness.  

  • Perhaps most importantly, unbiased information is scarce but that Diamond Nexus gemstones are a steal at $79 per carat

So, its apparently not CZ, but also not a lab-grown diamond.  This same news section has a number of articles talking about 'synthetic polycrystalline diamond', but that doesn't make much sense since we now know that polycrystalline diamond has little in the way of desirable optical properties.

Confused, we go to their FAQ to learn more.  We find some answers here:

{Screenshot,, 11/15/2007}

From this we can see that it contains ingredients that are also used in making Cubic Zirconium (Zr, Y, O), but its apparently 'polycrystalline' and contains Carbon.  We also learn that the terms to describe "diamond stimulants" are generally obsolete.  Further reading shows:

{Screenshot,, 11/15/2007}

Curiously, while they claim multiple labs have confirmed what is in their product, they are unwilling to cite which labs they are, or provide any other supporting data for this claim.   

With Diamond Nexus insisting that their gemstones were a breakthrough only recently available, advertising as if their product is a lab grown diamond, combined with their challenge that no one had bothered to actually test their product via a materials engineer, we decided to spend some money and see what information an independent evaluation would find.  We wanted to be able to make a 'bona fide statement' as per Diamond Nexus' request when people asked what the Diamond Nexus product is.

Towards that end, we contacted Anderson Materials Evaluation Inc. , a leading materials evaluation laboratory, and asked them to independently purchase a Diamond Nexus Gemstone directly from Diamond Nexus (they simply went to the Diamond Nexus site and ordered a stone using a personal credit card, and had it shipped directly to their lab), and subject the stone they received to Xray Photoelectron Spectroscopy [XPS] (a more sensitive testing method than the XFS Diamond Nexus mentioned) in order to settle the question of what the Diamond Nexus Gemstone really is.  You can learn more about XPS testing here.  

While Anderson Materials has three PhD's on staff, we were fortunate to have Dr. Anderson himself run the testing on the Diamond Nexus Gemstone.  Dr. Anderson has over 35 years of surface analysis experience, and nearly 30 years experience with XPS.  He has served as an officer of the ASTM Committee E-42 on Surface Analysis and an U.S. Expert on several sub-committees of the ISO Technical Committee 201 on Surface Chemical Analysis. He worked for Case Western Reserve University as a post-doctoral fellow, the Dept. of the Navy as a research physicist, and Martin Marietta and Lockheed Martin as a senior scientist before founding AME, Inc.  In short, you'd be hard pressed to find a better person to help you characterize an unknown material.

The results?  

Independent laboratory testing found the Diamond Nexus Lab product to be.... ordinary cubic zirconia.  

The same material Diamond Nexus claimed was not worthy of fine jewelry and chided other sellers for not being upfront about.  Far from a scientific advancement or breakthrough only recently available in the US as claimed, and not man-made diamond as advertised, not polycrystalline compound, etc.  

Here are some excerpts from the report:

  • "The principal elements of the gemstone are zirconium, yttrium, and oxygen, so the gemstone is a common cubic zirconia."

  • "No Hf, Fe, Ni, or Co were detected, despite Diamond Nexus Labs listing them as present in the FAQ's page of their website."

  • "Immediately after sputtering the surface with argon ions, the carbon concentration was almost zero...During the measurement we observed the carbon concentrations on the surface to increase.  This increase was due to the adsorption of hydrocarbons in the XPS system, despite its great vacuum, onto the surface. Cubic zirconia is very inclined to bond to carbon and hydrocarbons."  

  • "An excess of oxygen was observed on the surface.  This may be due to the reaction which can cause cubic zirconia to become cloudy and is observed here in an early stage due to the great surface sensitivity of XPS."  [Comment: one benefit of the Asha's amorphous diamond coating is to prevent this reaction]   

  • "The claim that the gemstone is polycrystalline must come from a misunderstanding on their part.  A cubic zirconia gemstone which was polycrystalline would be very undesirable...The polycrystalline material is good for furnace bricks, but not for gemstones, especially given their claim to make the World's Finest Diamond Simulant Gemstones."

You may review the full report at your leisure here (PDF format).  Please note that this report remains the property of 

We hope this information is useful to those currently interested in diamond simulants and who don't want to be confused as to what they are actually purchasing. 

Feel free to discuss on our message boards here

End report...plug for our Asha® diamond simulant begins below to help recoup the thousands spent on the above report and legal review for publishing it.  

Why is Asha® the most realistic diamond simulant?

Asha® is unique because it the only simulant in the world that employs true lab created amorphous diamond (pure carbon diamond bonds) in its construction.

Ashas being loaded for the amorphous diamond infusion process

Because Asha contains actual diamond carbon bonds, the result is a diamond simulant that is at last able to truly mimic the light play and beauty of gem diamond but at diamond simulant pricing.

The end-result:  Just as cultured pearls offer you the beauty of pearls at a fraction of the natural pearl price, Asha® is able to offer you the brilliance and beauty of real diamond, but at a fraction of the natural diamond price.

We invite you to browse our website and learn more about our Asha diamond simulant.  

In keeping with the beauty and realism of the Asha, we only utilize high-end, heavyweight jewelry mountings suitable for holding the finest of natural diamonds for our jewelry offerings.



"I got my princess cut earrings today and they are the most gorgeous earrings 
I have ever had

These diamonds are more sparkly than my engagement ring which is a natural D/VS1 diamond! They are simply breathtaking! These are classy and made to perfection.

Thanks so much! This is my second purchase with you and not my last!"

Customer testimonial, reprinted with permission.  Lots more testimonials here.

All the beauty of diamond stud earrings but for only $269?  

Seeing is believing!  Try our #1 selling 1.5ctw, 14k White Gold Asha® Princess 
stud earrings for only $269!
save over $130, plus free 2 day UPS shipping.

Details here!

Recommended next steps:

Looking for a stunning gift (all the beauty of diamond stud earrings or a diamond pendant 
but for less than $400?) and need it quickly?  
Visit our Ready To Ship Jewelry page here.

Just learning about diamonds and diamond simulants (moissanite, CZ, Asha, etc)?  
Visit our "Top Diamond Simulant Myths" article here.

We also invite you to browse our website for further education, shopping, read our many 
customer testimonials here
, or even interact with some of our many customers directly on our 
very popular message boards (300,000+ posts!) here.

Asha® is our registered mark 
Content and images, copyright 2007,