Is Moissanite Stronger Than Sapphire?

When it comes to durability in gemstones, moissanite and sapphire are both highly valued materials. Both are known for their exquisite hardness and durability, making them excellent choices for jewelry. However, the question remains: is moissanite stronger than sapphire?

Hardness: The Mohs Scale

One of the primary factors in determining the strength of a gemstone is its hardness. Gemologists use the Mohs scale of mineral hardness, which ranges from 1 (talc) to 10 (diamond). Both moissanite and sapphire are rated high on this scale:

Moissanite: 9.25 Sapphire: 9

While moissanite has a slightly higher hardness score than sapphire (9.52 on the Mohs scale), the difference is minimal. However, this higher hardness means that moissanite is slightly more resistant to scratches.

Toughness: The Ability to Withstand Impact

Toughness refers to a material's ability to withstand impact without breaking. Both moissanite and sapphire are considered durable and tough, but moissanite tends to have a slight edge:

Moissanite's crystal structure provides better toughness compared to sapphire, which can be more brittle due to its inclusions. The presence of inclusions in natural sapphire can make it more susceptible to chipping or cracking, although lab-grown sapphire or very clean natural sapphire might exhibit similar toughness to moissanite.

Overall Durability and Heat Resistance

Both moissanite and sapphire are highly durable and can withstand a wide range of temperatures and chemicals:

Heat Resistance: Both can withstand temperatures up to 2000°C without degrading. Chemical Resistance: Both are infusible and insoluble in acids and other chemicals.

The only notable difference is in their reaction to pure oxygen, where moissanite will burn at 1200°C, while sapphire remains unaffected. In this specific scenario, sapphire has the edge, but this is a rare and improbable condition.

Conclusion

While both moissanite and sapphire are extremely durable and hard, moissanite stands out in terms of both hardness and toughness. Its higher hardness score on the Mohs scale, along with a more resistant crystal structure, make it a stronger material in most practical jewelry applications.

For a more comprehensive comparison, consider the following key points:

Hardness: Moissanite (9.25) vs. Sapphire (9.0) Toughness: Slight edge to moissanite due to crystal structure Durability in Heat and Chemicals: Equal, both are highly resistant

In conclusion, if strength is your primary concern, moissanite is indeed a stronger choice than sapphire. However, sapphire may still be preferred based on its more traditional appearance and historical reputation as a gemstone.