Lab Diamond vs Moissanite Singapore: An Honest Comparison
Moissanite is the most common diamond alternative in the engagement ring market, and the comparison between moissanite and lab-grown diamonds comes up regularly at Diamond Ateliers. Both are visually similar to white diamonds, both are significantly cheaper than natural diamonds, and both are durable enough for daily wear as an engagement ring. But they are fundamentally different materials with different optical properties, different hardness, and different market positioning. This guide covers the honest differences so you can make an informed decision.
What Is Moissanite?
Moissanite is silicon carbide — a completely different chemical compound from diamond, which is pure carbon. It was first discovered in 1893 by Henri Moissan in a meteor crater in Arizona. Natural moissanite is extraordinarily rare; virtually all moissanite used in jewellery today is lab-created. It is not a diamond simulant in the way cubic zirconia is — it is a distinct gemstone with its own properties, and it happens to be visually similar to diamond in some respects while being distinctly different in others.
What Is a Lab-Grown Diamond?
A lab-grown diamond is chemically, physically, and optically identical to a natural diamond. It is pure carbon arranged in a diamond crystal structure, grown in a laboratory under conditions that replicate the heat and pressure of diamond formation in the earth. A lab-grown diamond and a natural diamond are the same material — the only difference is origin. A gemologist cannot distinguish one from the other without specialised equipment.
The Key Differences
Hardness
Diamond rates 10 on the Mohs scale — the hardest natural material known. Moissanite rates 9.25, making it the second hardest gemstone used in jewellery. Both are highly scratch-resistant and appropriate for daily wear. In practice, the difference in hardness between 9.25 and 10 has minimal impact on how either stone performs as an engagement ring in normal conditions.
Brilliance and Fire
This is where moissanite and diamond diverge most visibly. Moissanite has a higher refractive index than diamond (2.65 vs 2.42) and significantly higher dispersion (0.104 vs 0.044). This means moissanite produces more rainbow-coloured fire than diamond — more colour flashes, more colourful sparkle. Under certain lighting conditions, particularly direct sunlight or bright artificial light, moissanite can appear almost disco-ball-like in its colour dispersion. Diamond's sparkle is white and silver — scintillation. Moissanite's sparkle adds coloured fire on top of that.
Whether this is desirable or not is personal. Some clients love the additional fire. Many clients, particularly those who have compared both stones in person, find moissanite's fire to be obviously different from a diamond's and prefer the cleaner, more restrained brilliance of a diamond.
Colour
Moissanite stones used to have a slight yellow or green tint under certain lighting. Modern premium moissanite (often marketed as "Forever One" or "DEF colour" equivalent) has largely addressed this, though some clients still notice a slight warmth in moissanite that is not present in a high-colour diamond. Lab-grown diamonds are available in D-F colour with no tint whatsoever.
Price
Moissanite is significantly cheaper than lab-grown diamonds of equivalent size. A 2ct round moissanite might cost SGD 500–800. A 2ct round lab-grown diamond of good quality typically costs SGD 3,000–6,000+. The price gap is substantial and is the primary reason clients consider moissanite.
Identity and Perception
A lab-grown diamond is a diamond — it can be described as such with complete accuracy. Moissanite is not a diamond and should not be described as one. For clients for whom it matters that their ring contains a diamond, lab-grown is the answer. For clients who are comfortable with a different stone that looks similar, moissanite is a viable choice at a lower price point.
Our Position at Diamond Ateliers
We work with lab-grown diamonds. We do not work with moissanite, not because moissanite is inferior as a material, but because our clients are specifically seeking diamonds — and lab-grown diamonds give them exactly that at a fraction of the cost of natural stones. The combination of diamond identity, identical physical properties, and accessible pricing makes lab-grown the right answer for the vast majority of our clients.
If a client specifically asks about moissanite, we have this conversation honestly and help them make the right decision for their situation. We have no interest in selling a client something that is not right for them.
Frequently Asked Questions
Can a jeweller tell moissanite from a diamond?
Yes, with the right tools. A standard diamond tester (which measures thermal conductivity) will actually pass moissanite as diamond because moissanite's thermal conductivity is similar to diamond's. However, a moissanite-specific tester or a gemologist with a loupe can distinguish them by observing moissanite's characteristic doubling of facets under magnification — a property unique to doubly refractive stones like moissanite.
Does moissanite hold its value?
No more than lab-grown diamonds do. Both are primarily purchased for wearing, not investment. The resale market for moissanite is very limited. Neither moissanite nor lab-grown diamonds should be purchased with any expectation of resale value.
If budget is very tight, is moissanite a reasonable choice?
Yes, with full information. If the budget genuinely does not stretch to a lab-grown diamond of the desired size, moissanite is a hard-wearing, visually attractive stone that is significantly better than a very small or low-quality diamond. The key is making the choice knowingly rather than having moissanite presented as equivalent to diamond when it is not.