Gemstone Hardness & the Mohs Scale Explained
Why some stones survive daily wear and others don't — it's all about hardness.
When choosing a stone for an everyday ring, hardness matters. The Mohs scale is the simple system used to compare how scratch-resistant gemstones are. Here's how it works.
What the Mohs scale is
The Mohs scale rates mineral hardness from 1 (softest) to 10 (hardest). A higher number means better resistance to scratches — important for jewelry worn every day.
Where common stones land
| Stone | Mohs hardness |
|---|---|
| Diamond | 10 (hardest) |
| Moissanite | Around 9.25 — second only to diamond |
| Sapphire / Ruby | 9 |
| Emerald | Around 7.5–8 |
Why moissanite scores so well
At around 9.25, moissanite is one of the hardest gemstones available — making it superb for everyday rings and earrings. More in Is Moissanite Durable Enough?
Hardness vs toughness
Hardness measures scratch resistance, not resistance to chipping (toughness). Most fine jewelry gems are both hard and reasonably tough — just avoid hard knocks regardless.
FAQs
How hard is moissanite on the Mohs scale?
Around 9.25 — second only to diamond, making it excellent for daily-wear jewelry.
What's the difference between hardness and toughness?
Hardness is scratch resistance; toughness is resistance to chipping or breaking. Both matter for everyday jewelry.
Leave a comment