Lab-Grown Diamonds vs Cubic Zirconia and Moissanite

It's easy to lump lab-grown diamonds in with cubic zirconia (CZ) or moissanite — but they're not the same category of stone at all.

The Key Distinction

CZ and moissanite are diamond simulants: different minerals, grown or manufactured to look like a diamond. A lab-grown diamond is not a simulant — it's chemically, physically and optically an actual diamond.

How They Compare

Diamond (lab-grown or mined) rates 10 on the Mohs hardness scale, the hardest known natural material. Moissanite rates around 9.25, and CZ around 8–8.5 — both noticeably softer, meaning more visible wear over years of daily use. Diamonds also handle light differently, giving a distinct brilliance and fire that simulants approximate but don't fully replicate.

Why It Matters for Daily Wear

A piece meant to be worn constantly — and eventually passed down — needs to hold up to that use. Hardness and durability are exactly where a genuine diamond, lab-grown or mined, outperforms a simulant over time.