Can You Tell If It Is A Natural Or Lab Diamond?

This post includes excerpts from an article originally published online by JCK in 2021.

We are increasingly asked how a natural diamond can be distinguished from a lab created stone.

It is both a very good and extremely important question. After all, with the difference in value between a large high grade natural diamond and an equivalent grade lab grown diamond being tens of thousands of pounds, there is a lot riding on it.

And the reality is that it is an increasingly challenging task, and of which the diamond grading institutes are acutely aware.

Unsurprisingly, they often are called upon to verify whether a particular diamond is naturally formed or lab created, with fraudsters endeavouring to match lab grown diamonds with the precise grading specifications of existing natural diamonds' GIA and IGI certificates.

To quote Tom Moses, the executive vice president of the GIA, one of the world's most respected grading institutes “What seems to be occurring with more frequency is people are being very careful in making the copy as close to the original as possible.

So if you take a look at the report data and you take a look at the stone, look at the colour, look at the proportions, the girdle thickness, and put it on the scale, you’ll find they are virtually the same.

[The cheaters] are being extremely careful at finding matches for material that mimics the natural diamond.”

However, the GIA and the IGI say they can identify all lab grown diamonds using highly specialised scientific equipment.

And in some cases, certain lab-grown diamonds have bluish, greenish or brownish tinges—due to treatments or boron doping—which could be a possible clue, although Moses notes some natural diamonds have these tinges too. (read more about BGM here).

“It isn’t always such a red flag that most people would notice it,” he says.

The GIA also now offers a low-cost update and verification service to both the trade and the public.

Moses says that they are also working on an “imaging system where a dealer could take the captured image of the diamond and send it to the cloud and, using artificial intelligence and algorithms, we would be able to say, ‘Yes, that is the diamond that we graded,’ or ‘No, that is not the diamond we graded.’ I believe that will essentially make this issue go away.”

This pragmatic and proactive approach adopted by the grading institutes is certainly reassuring. 

Nevertheless, it demonstrates that even the most respected grading labs in the world are only able to tell the two types of diamond apart by remaining at the very top of their game.


Read more about lab grown diamonds

Read more about diamond grading and certification