The Mohs scale: understanding the hardness of your natural stones
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The Mohs scale measures mineral hardness from 1 (fingernail) to 10 (diamond). The harder a stone is, the more resistant it is to scratches and water. Below 5, avoid water. Above 6, a brief rinse with fresh water is generally fine.
For Eclatoria jewelry: amethyst (7), jasper (6.5-7), agate (6.5-7), labradorite (6-6.5), turquoise (5-6), lapis lazuli (5-6), mother-of-pearl (3.5-4).
What is the Mohs scale?
The Mohs scale was created in 1812 by the Austrian mineralogist Friedrich Mohs. He classified 10 reference minerals from softest to hardest, from 1 (talc) to 10 (diamond). The rule is simple: a mineral scratches all those below it on the scale.
It is not a linear scale. The jump between 9 (corundum, ruby, and sapphire) and 10 (diamond) is much greater than the jump between 1 and 2. And hardness says nothing about impact resistance: a very hard stone can easily crack if it falls.
Eclatoria stones on the Mohs scale
| Stone | Mohs Hardness | Fresh water? |
|---|---|---|
| Amethyst | 7 | ✓ Brief rinse OK |
| Dalmatian Jasper | 6.5-7 | ✓ Brief rinse OK |
| Indian Agate | 6.5-7 | ✓ Brief rinse OK |
| Labradorite | 6-6.5 | ✓ Brief rinse OK |
| African Turquoise | 5-6 | ⚠️ With caution |
| Lapis Lazuli | 5-6 | ⚠️ With caution |
| Sunstone | 6-7 | ✓ Brief rinse OK |
| White Mother-of-Pearl | 3.5-4 | ⚠️ Stream of water only, dry immediately |
Important reminder: even for water-resistant stones, prolonged soaking, salt water, and chemical products (perfume, cream, chlorine) should be avoided. For jewelry mounted on stainless steel, the steel itself is quite water-resistant. It is the stones that dictate the precautions.
What hardness changes for maintenance
To purify your stones, you don't have to use water. Fumigation (white sage, palo santo) works for all stones without exception. The flower of life also works. These two methods are universal and risk-free.
Hard stone (6.5+): brief running water possible, fumigation, flower of life, lunar or solar light.
Soft stone (less than 6): fumigation or flower of life recommended. If using water, a very brief rinse and immediate drying.
White Mother-of-Pearl: gentle stream of fresh water only, dry immediately. Never salt, never soak.
Frequently Asked Questions
No. Hardness measures scratch resistance, not impact resistance. A very hard stone like quartz or amethyst can definitely crack if it falls on tiles. Treat all your stones gently, even the most robust ones.
Mother-of-pearl is composed of thin layers of aragonite bound by organic proteins. Its hardness is only 3.5 to 4. Salt is abrasive and can create micro-scratches that irreversibly alter its iridescent reflections. That's why only a gentle stream of fresh water followed by immediate drying is recommended.
With caution. Its hardness of 5 to 6 makes it a bit more fragile. A very brief rinse under fresh water is possible, but avoid prolonged soaking. Its porosity also makes it sensitive to acids and chemicals. For purification, fumigation is the safest method.
Stainless steel itself tolerates water without problems. It is the stones mounted on it that dictate the precautions. For amethyst, jasper, or labradorite jewelry, a quick rinse with fresh water is possible. For mother-of-pearl, lapis lazuli, or African turquoise, it's better to stick to fumigation or the flower of life.
Find specific care instructions for each stone in our dedicated guides: amethyst, dalmatian jasper, labradorite, white mother-of-pearl.
In summary
- The Mohs scale classifies minerals from 1 to 10 according to their scratch resistance.
- Amethyst, jasper, agate: hardness 6.5-7, a rinse with fresh water is possible.
- White mother-of-pearl: hardness 3.5-4, stream of fresh water only, dry immediately.
- Hardness does not protect against impacts. All stones can crack if they fall.
- Fumigation and the flower of life work for all stones, without risk.
Do you want to know how to care for your specific stone?
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