Stuller Inc
Stuller Inc
Stuller Inc
Goto your account
Search Stories by: 

News, Feature Stories, Diamonds, The Great Diamond Debate

Articles from DIAMONDS BY TYPE - SYNTHETIC / LAB-CREATED (118 Articles)

Synthetic diamonds call for retailer awareness and caution

While lab-grown diamonds might provide benefits for jewellery retailers, BILL SECHOS says there are many potential pitfalls. Jewellers should be aware of the pitfalls. 

As synthetic diamonds gain a larger foothold in the marketpace the overriding issue for retailers is the need to be vigilant and aware. Man-made diamonds are here to stay, and they’re not going away. We’ve got to know what they are.

They are not an imitation like cubic zirconia and moissanite - they are diamonds and because of that, we must be more educated and a lot more aware.

Diamond imitations such as synthetic moissanite and synthetic cubic zirconia can be accurately identified by a trained jeweller or gemmologist using a 10x loupe and testing instruments.

However, the new synthetic (or man-made) diamonds are impossible to identify with a 10x loupe or normal equipment that is used for the CZ and moissanite. They are diamonds, so look like diamonds with a loupe and are identified as diamonds with the normal instruments.

"Man-made diamonds are here to stay, and they’re not going away. We’ve got to know what they are."

We’ve made the decision to invest in the high-tech equipment necessary to be able to positively identify a suspect stone as a high pressure/high temperature (HPHT) or chemical vapour deposition (CVD) diamond.

We have also built a reference collection of about 30 CVD and HPHT man-made diamonds ranging melée size to half carat for comparison and study purposes.

Over the last year we have been asked to test parcels of melée purchased at very low prices and unfortunately we discovered CVD stones.

We’ve had one case where five stones were identifed as man-made. We have had other instances where small stones turned out to be ‘suspect’. We’ve also had stones submitted for diamond certification without disclosure that turned out to be man-made.

If a large diamond submitted for certification is identified as a man-made diamond we will laser inscribe the girdle with a unique identification number and add it to the certificate registry and the ‘certificate check’ section on our website.

There are a number of concerns for retail jewellers arising from the advent of the latest synthetic diamonds.

These include;

  • Whether a large diamond purchased overseas without a recognised certificate submitted for a ring design might be man-made with the ramifications of being later identified as a synthetic after it’s left your premises.
  • Whether diamonds set in jewellery purchased ad stock purchases at overseas fairs where the prices are extremely competitive include synthetic diamonds,
  • Whether a piece of jewellery submitted for repair or valuation contains synthetic diamonds,
  • Whether a piece of jewellery being pawned or sold second hand contains synthetic diamonds

If the jeweller has suspiciouns, it’s not the end of the world because there are some very affordable safeguards they can take.

There are now inexpensive testing devices for only a few hundred dollars which can test both set and un-set stones and which provide the retailer a first warning to say there is something wrong with the stones and they need to be examined further.

These devices give you a red flag by identifying the diamond as a Type II diamond.

Currently all white synthetic diamonds are Type II, so if the stone does not pass this first test it’s rejected or should be sent to a well-equipped laboratory for further testing.

All white diamonds that are mined except for a very tiny percentage (less than 2 per cent) are Type I diamonds. So, if a diamond passes the first screen it can only be natural.

But there is a remote possibility that initial testing identifies a Type II diamond as synthetic even though it’s a natural diamond. CVD man-made diamonds are often brown out of the manufacturing chamber and are post treated with HPHT to make them white. There are rare occasions where natural brownish Type II diamonds are whitened by the same process to make them “D, E or F.”

However, because they are Type II diamonds, these stones can also be flagged by using the same very affordable instruments mentioned above before further testing is done. So, there’s quite a bit of safeguard that the jeweller can take for a relatively small investment in equipment and which is very easy to use.

Another issue concerning man-made diamonds is that there’s a perception that because they’re manufactured in a factory, they are all equal or identical. We’re starting to learn all man-made diamonds are not equal, they’re not the same quality, even within the same factory, let alone from different factories using different equipment.

This makes them more believable because they have different levels of inclusions that differ from one stone to another, much like mined diamonds.

So, consumer education around this is very important. Jewellers need to understand this themselves so they can discuss it with customers. It’s intersting that De Beers’ advertising sounds like the stones they release – as opposed to manufacture – will all be of the same or similar quaility.

De Beers is promoting a consistent quality, almost identical for all their stones which is why they won’t need to be graded.

It’s early days and the steps De Beer’s has taken to enter the synthetic market are very significant and we don’t know what sort of impact it will have in the industry until it gains a bigger foothold.



'The Great Diamond Debate' Contents » 

Innovation vs Disruption: Spectators don't win games
Coleby Nicholson, managing editor of Jeweller
Diamonds and Youth: Millennials and Gen Z drive sales
Predicting a synthetic future
Garry Holloway, owner Holloway Diamonds
Lab-created diamond jewellery market to grow to US$15B by 2035
Paul Zimnisky, - indepdendent analyst


Bill Sechos

Managing Director • Gem Studies Laboratories

Bill Sechos is managing director of Sydney-based Gem Studies Laboratory, the Gemmological Association of Australia’s (GAA) endorsed diamond grading laboratory. He holds a science degree from the University of Sydney and has served as the GAA president and chairman of the GAA Board of Studies and Examinations. For more information visit:

Showcase Jewellers (JIMACO)

Read current issue

login to my account
Username: Password:
Jeweller Magazine
Rapid Casting
Rapid Casting
© 2024 Befindan Media