Answer: Moissanite, lab‑grown diamonds and cubic zirconia are all alternatives to natural diamonds, but they differ in composition, hardness and value. Lab‑grown diamonds are real diamonds created in a lab with the same properties as natural diamonds; moissanite is a separate gemstone (silicon carbide) known for its high refractive index and durability; cubic zirconia is a synthetic diamond simulant that is less durable and more affordable. Choose based on budget, ethical preferences and desired sparkle.
Key Points
- Moissanite: Composed of silicon carbide; hardness about 9.25 on the Mohs scale; very brilliant with strong rainbow fire; more affordable than diamonds; durable enough for everyday wear.
- Lab‑grown diamonds: Carbon crystals grown in a laboratory; hardness 10 (same as natural diamonds); visually identical to mined diamonds; typically 30–50% cheaper than natural diamonds; hold some resale value.
- Cubic zirconia: Made of zirconium dioxide; hardness about 8‑8.5; looks like a diamond but with less scintillation; very inexpensive; can scratch and cloud over time.
- Price & Value: Lab‑grown diamonds cost the most but retain value; moissanite offers a balance of brilliance and affordability; cubic zirconia is budget‑friendly but not durable.
Gemstone Comparison
| Gemstone | Composition | Hardness (Mohs) | Appearance | Price Range | Best For |
| --- | --- | --- | --- | --- | --- |
| Lab‑grown diamond | Carbon (same as natural) | 10 | Identical to mined diamond | Highest | Proposals & long‑term wear |
| Moissanite | Silicon carbide | 9.25 | Very brilliant with rainbow fire | Medium | Affordable engagement rings |
| Cubic zirconia | Zirconium dioxide | 8‑8.5 | Diamond‑like but less sparkle | Low | Fashion/costume jewellery |
FAQs
Is moissanite a real diamond?
No. Moissanite is a separate gemstone made of silicon carbide. It resembles diamond but has different composition, hardness and optical properties.
Does cubic zirconia last?
Cubic zirconia can scratch and become cloudy with daily wear. It’s best suited for occasional or fashion jewellery; for everyday wear, choose moissanite or a diamond.
Are lab‑grown diamonds ethical?
Yes. Lab‑grown diamonds avoid the environmental and social issues of mining. They are considered a sustainable and conflict‑free choice, but make sure they come with certification from IGI, GIA or another reputable lab.