Three white stones sit on a velvet tray. To most eyes, all three sparkle beautifully. Yet one was formed deep in the earth over a billion years, one was grown in a laboratory in a matter of weeks, and one isn't a diamond at all. Knowing which is which, and why it matters, is the key to choosing the right stone for you.
The short answer: lab-grown and natural diamonds are both real diamonds, chemically and physically identical, and differ only in origin and price. Moissanite is a different gemstone, silicon carbide, that is slightly softer and shows noticeably more rainbow-coloured fire. For an engagement ring that looks and behaves exactly like a diamond, at a more accessible price, lab-grown diamond offers the strongest balance of beauty, durability and value.
At a Glance: The Three Stones Compared
|
Property |
Natural diamond |
Lab-grown diamond |
Moissanite |
|---|---|---|---|
|
Composition |
Carbon |
Carbon |
Silicon carbide |
|
Hardness (Mohs) |
10 |
10 |
9.25 |
|
Refractive index |
~2.42 |
~2.42 |
~2.65 |
|
Dispersion (fire) |
~0.044 |
~0.044 |
~0.104 |
|
Look |
Classic white brilliance |
Identical to natural |
Intense rainbow fire |
|
Graded on the 4Cs |
Yes |
Yes |
Not by major diamond labs |
|
Relative cost |
Highest |
Significantly lower |
Lowest |
|
Origin |
Mined |
Laboratory-grown |
Laboratory-created |
Natural Diamonds: Rarity and Romance
Natural diamonds formed under immense heat and pressure deep beneath the earth's surface. Their appeal is rooted in rarity, geological history and tradition.
Why people choose them:
- The romance of a stone billions of years in the making.
- A long-standing tradition in engagement and heirloom jewellery.
- A connection to Southern Africa's deep diamond heritage.
What to consider:
- The highest price per carat of the three.
- Origin and traceability vary; ask about provenance.
Lab-Grown Diamonds: Identical Stone, Smarter Price
Lab-grown diamonds are created using CVD (Chemical Vapour Deposition) or HPHT (High Pressure, High Temperature) processes that replicate the conditions in which natural diamonds form. The result is real diamond, atom for atom.
Why people choose them:
- Identical hardness, brilliance and fire to a natural diamond.
- Indistinguishable to the naked eye; specialist equipment is needed to identify origin.
- A significantly lower price, allowing a larger or higher-grade stone within the same budget.
- Clear, documented origin.
- Graded by independent laboratories, most commonly IGI, using the 4Cs.
What to consider:
- Lab-grown diamonds don't carry the rarity of natural stones, which affects resale value.
Moissanite: Brilliant, But Different
Moissanite was first discovered in meteorite fragments by Nobel-winning chemist Henri Moissan in the 1890s. Natural moissanite is extremely rare, so all moissanite used in jewellery is laboratory-created.
Why people choose it:
- The most affordable of the three.
- Very hard and durable, suitable for daily wear.
- Exceptional fire: more than twice the dispersion of diamond.
What to consider:
- That intense rainbow sparkle is distinctive, and some people find it reads as less like a diamond, especially in larger stones and bright sunlight.
- It's a different gemstone, not a diamond, and isn't graded on the diamond 4Cs by major diamond laboratories.
- Slightly softer than diamond.
Sparkle, Explained
Three terms describe how a gem plays with light:
- Brilliance: the white light reflected back to your eye.
- Fire: the flashes of spectral colour created as light splits.
- Scintillation: the sparkle and pattern of light and dark as the stone moves.
Diamonds, natural or lab-grown, balance crisp white brilliance with flashes of fire. Moissanite's higher refractive index and dispersion produce a more intense, more colourful display. Neither is "better"; they're different aesthetics. For a ring that looks like a classic diamond, choose a diamond.
Which Stone Is Right for You?
|
If you value... |
Choose |
|---|---|
|
Rarity, tradition and geological romance |
Natural diamond |
|
A real diamond with maximum size and quality for your budget |
Lab-grown diamond |
|
The lowest cost and intense colourful sparkle |
Moissanite |
|
A diamond for an engagement ring you'll wear for life |
Natural or lab-grown diamond |
|
Clear documented origin |
Lab-grown diamond |
Durability for Everyday Wear
An engagement ring is worn through dishes, gym sessions, gardening and travel. All three stones are hard enough for daily wear, but diamond's 10 on the Mohs scale means it resists scratching better than any other gemstone. Remember, though, that hardness isn't toughness: any stone can chip if struck hard at the wrong angle. A protective setting, such as a bezel or low claws, matters as much as the stone.
Frequently Asked Questions
Is moissanite a fake diamond? Moissanite isn't a fake diamond; it's a different gemstone, made of silicon carbide. It's very hard and brilliant, but it has more rainbow-coloured fire than a diamond and different optical properties.
Can you tell the difference between a lab-grown and a natural diamond? Not with the naked eye. Lab-grown and natural diamonds are chemically, physically and optically identical. Gemmological laboratories use specialist equipment to determine origin.
Is lab-grown diamond or moissanite better for an engagement ring? For a ring that looks exactly like a classic diamond, lab-grown diamond is the stronger choice: it is a real diamond, scores 10 on the Mohs scale and is graded on the 4Cs. Moissanite suits buyers who want the lowest cost and love colourful sparkle.
Do lab-grown diamonds last forever? Yes. Lab-grown diamonds have the same hardness and durability as natural diamonds. With normal care and occasional cleaning, they'll last for generations.
Conclusion
Natural diamond, lab-grown diamond or moissanite: each has its place. If you want a real diamond with exceptional value, lab-grown is hard to beat; if rarity speaks to you, natural remains timeless; if budget and fire lead, moissanite delivers. The right choice is the one you'll love every time you look down.
PURA designs bespoke engagement rings and fine jewellery with certified lab-grown diamonds. Visit pura.co.za to compare stones with our team and find the one that's unmistakably yours.