Diamond vs Moissanites comparison
Jan 30, 2023
Lab Diamonds vs Moissanites, Truth vs Lies: Which is the Better Choice?


Michael, one of our top gemmologists at Novita, was asked to write a brief yet insightful article to clarify the misconceptions about diamonds vs moissanites. With moissanites, there are companies that specialise in selling these diamond simulants. As a result, unfortunately, there is quite a lot of misleading information characterising moissanites. So we want to clarify the truths. 


In short - they look different. Here we will explain the differences in simple terms so you could start seeing them too. 

It is common for moissanites to have tints. If you evaluate a moissanite using the same colour grading as applied to diamonds which is “D” to “Z” scale, you’ll see that it is on average a “J” in colour. This colour is not recommended in diamonds because it shows a significant tint of brown colour which is clearly visible to the naked and untrained eye.

Sadly, there are a lot of companies that try to take advantage of uneducated people, by claiming to offer “H” colour moissanites which haven't yet been verified by the industry experts. As a gemmologist I have had the opportunity to see many of those moissanites none of which appear to be “H” in colour.


Why Do Lab Diamonds Sparkle Differently Than Moissanites?

Moissanite sparkles are unique and look like rainbow colours. When comparing diamonds and moissanites one more thing stands out to the naked and untrained eye. It is the difference in the sparkles’ colours. While diamonds’ sparkles are white, moissanites produce iridescent colours. This significant difference in colours occur due to moissanites being pleochroic - showing two or three colours when viewed from different angles. 


How Does Double Refraction Affect Moissanites Compared to Lab Diamonds?

The optical properties of diamonds are such that they don’t change the colour when being viewed from different angles. By contrast, all moissanites do have different colour appearances as they are double refractive. This part gets a bit more technical but don’t worry, we’ll stick to simple terms. This peculiarity is only found in moissanites and never in diamonds. To put it simply the easiest way for you to notice it is to examine a moissanite from its top taking a close look to where the facets join. You’ll notice that instead of seeing just one joint, you’ll spot two.


Debunking Disinformation from Simulant Industry: Can Cutting Techniques Eliminate Double Refraction in Moissanites?

Be aware of companies that claim they found a new way of cutting a moissanite which stops double fraction from happening. This information has yet been highly doubtful as double fraction does not come from the way a stone is cut but comes instead from the material it is made of.

Moissanites vs diamonds the truth

Any Other Differences Between Lab Diamonds and Moissanites?

Colour change in moissanites. The easiest way to test this is by bringing the stone close to direct fire for a few seconds. This will make the stone go green in colour.

Moissanites have smooth girdles whereas Diamonds have faceted girdles. Diamonds in general are cut differently - given the price tag of a diamond a lot more effort goes into the cutting of one. 

Diamonds are harder than moissanites. In fact, diamonds are the hardest material found in nature. It is true that diamonds are forever. Moissanites, however, are the hardest out of all other simulants such as cubic zirconia, etc. Yet, moissanites are three times less hard than diamonds, which makes the former tend to scratch easier. Another way to differentiate diamonds from moissanites is that the latter are denser and heavier, which makes the former more comfortable to wear.

Lab Diamonds Vs Moissanites: Truth or False?

TRUE: Moissanites have a brown tint in colour on average, “J” when comparing it to a diamond colour grading system.
FALSE: Moissanites can be made white in colour (colourless).
TRUE: Moissanites sparkles are iridescent in colour while diamonds’ sparkles are white.
FALSE: Moissanites sparkle similarly or identical in colour to diamonds.
TRUE: All moissanites suffer from double refraction no matter how they are cut or polished.
FALSE: There is a way to cut moissanites to eliminate double fraction.
TRUE: Moissanites resemble costume jewellery due to the iridescent sparkles they produce.
FALSE: Moissanites are cut to the same standards as diamonds.
TRUE: Moissanites go green when exposed to direct fire.

Note: As we explain in detail in our lab grown diamonds guide, the typical moissanite tester in the market cannot be used to test lab diamonds. Beware of dishonest jewellers pulling tricks on naive customers, its done by using a moissanite testers on lab diamond rings to show a false reading as if the lab grown diamond was a moissanite.  


In summary

Diamonds and moissanites look different due to various factors. Moissanites tend to have tints and are often "J" in color, while diamonds can be colorless. Moissanites produce iridescent sparkles, while diamonds exhibit white sparkles. Moissanites exhibit double refraction due to their material, and this property cannot be eliminated by cutting or polishing. Moissanites are also denser and heavier than lab made diamonds in UK, making them less comfortable to wear. Lab created diamonds in UK are harder, making them more durable. Some companies may provide misleading information about moissanites, so it`s essential to be aware of the differences.