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Can You Tell The Difference Between a Moissanite and a Diamond?

The difference between moissanite and diamond is definitely subtle, but it is noticeable if you know what you are looking for. Moissanite is a gemstone in its own right and has its own beauty, but when compared with diamond, it exhibits an extra level of sparkle and fire which diamonds don’t have. For some people, this makes moissanite even more desirable than diamonds!

Brilliance and Fire

Brilliance and Fire are the most obvious differences when comparing moissanite and diamond. Brilliance is the small flashes of white light that you can see being reflected from inside the stone back to you, and fire is the way white light disperses into different colours as it travels through the stone to give you that rainbow effect.

Put simply, when light enters a clear substance like moissanite, it gets slowed down, which causes it to bend or refract, before it speeds up again as it leaves the substance. Moissanite has a higher Refractive Index than diamond, which means that moissanite will bend light more, and therefore show higher levels of Brilliance and Fire.

This means that when sunlight hits a moissanite stone, it sparkles in a rainbow, almost disco ball pattern that is beautiful to behold. A diamond, on the other hand, will refract light in more of a kaleidoscope pattern which sticks to a more white, blue, grey sparkle in the gem. The bigger the moissanite stone is, the easier it is to tell the difference in brilliance and fire of the gem from a diamond. However, in most cases, people will simply be admiring your moissanite engagement ring for the beautiful piece that it is, not just checking the sparkle of the main gem to see what type of gemstone it is.

Cullen Jewellery Engagement Ring
Cullen Jewellery Engagement Ring on hand


A colourless moissanite stone and a diamond are slightly different in colour, but the difference is so small that it is only noticeable when comparing moissanite and diamond side by side. A diamond will have no traces of other colours, whereas a moissanite stone may have subtle traces of grey or yellow that can be seen in certain lights. Unless you have a moissanite ring and a diamond ring side by side, this difference is impossible for regular people to notice.

In contrast, being a lab grown stone, moissanite is easy to colour, allowing you greater flexibility in design with a moissanite engagement ring. Some popular colours are pink, blue, yellow, purple, green, grey, but a moissanite stone can be coloured to your heart’s desire.


This is a popular discussion point when comparing moissanite vs diamond, but one that people will not be able to spot while looking at your engagement ring. Moissanite is lab grown, so they generally have almost no flaws. Diamond, on the other hand, is often mined and many of the gems will have flaws, meaning that unless you want to pay top dollar, the gem in your engagement ring will have imperfections.

Our moissanite stones have a clarity of VVS1-2, which stands for very very slightly included. An inclusion is a small imperfection trapped within the stone which can block the path of light through the stone, causing it to show less brilliance and fire, and look more dull. A grading of VVS1-2 is nearly perfect on the clarity grading scale, meaning your stone should sparkle and shine beautifully. Finding a diamond, however, with a VVS1-2 grading is quite difficult and extremely expensive. For comparison, where you could purchase a VVS1-2 7.5mm (1.50ct) Round cut moissanite for around $900 AUD, those same specifications for a diamond would set you back at least $8000 AUD.

Browse Moissanite Collection
Cullen Jewellery Engagement Ring on hand


Overall, most of these differences between moissanite rings and diamond rings are not something that ordinary people would spot unless comparing rings side by side. The extra brilliance and fire is the only difference that someone who knows about moissanite would be able to spot, but since when is extra sparkle a bad thing?! Many people fall into the trap of thinking of moissanite as “fake diamonds”, but we believe it is its own stone and beautiful in its own right.