Moissanite vs Lab Diamond: Honest Comparison

By Olivia Chen · October 1, 2026

The Core Difference

Moissanite is silicon carbide. Lab diamonds are real carbon diamonds grown in controlled environments. Both are ethical alternatives to mined diamonds, but they differ in key ways.

Brilliance and Fire

Moissanite has more fire (rainbow flashes) than diamond due to its higher refractive index (2.65 vs 2.42). Some people love this extra sparkle; others find it too rainbow-like. Lab diamonds have the exact same optical properties as natural diamonds.

Hardness and Durability

Lab diamond: 10 on Mohs scale (hardest known material). Moissanite: 9.25 (very durable but slightly softer). Both are suitable for daily wear. Lab diamonds are more scratch-resistant over decades.

Price Comparison (1 carat round)

Mined diamond: $4,000-$8,000
Lab diamond: $800-$2,500
Moissanite: $300-$600

Color Grades

Lab diamonds come in all color grades (D through K+). Moissanite is typically near-colorless (G-H equivalent) but can show slight yellow or gray tints in certain lighting.

Which Should You Choose?

Choose lab diamond if you want identical properties to natural diamond at a lower price. Choose moissanite if budget is the top priority and you enjoy extra fire and sparkle.