Moh's Scale of Hardness
| Scale of Hardness |
Resilience |
Stones |
| 0-1 |
You can scratch this with your fingernail! |
Talc |
| 1-1½ |
You can scratch this with your fingernail! |
Gypsum Sulphur |
| 2-3 |
Amber |
|
| 2-4 |
Ivory |
|
| 3-4 |
Use a coin to scratch this (beware of metal beads) |
Pearl Coral |
| 3½-4 |
Malachite |
|
| 4 |
Use a knife to scratch this. |
Rhodochrosite |
| 4½ |
Can be scratched with a copper coin. |
Calcite Kyanite (lengthwise) |
| 5-6 |
Use a knife to scratch this stone and this stone scratches softer glass (watch out beads!). |
Fluorite Lapis Lazuli Turquoise |
| 5½-6½ |
Opal |
|
| 6-6½ |
Use a steel file to scratch this stone and this stone scratches harder glass (watch out glass beads!). |
Kyanite (across) Moonstone |
| 6½-7 |
Dust. Yes that’s right! Most dust is silicate (which is a 7) so make sure you clean all your gemstones below a 7 with a dust-free cloth. And no gardening without gloves if your rings have stones! |
Quartz Tanzanite Apatite Peridot |
| 7 |
Stone will scratch glass and previous stones listed. |
Citrine Amethyst |
| 7-7½ |
Tourmaline Garnet |
|
| 7½-8 |
Emerald |
|
| 8 |
This stone will scratch previous stones and quartz. |
Topaz |
| 8½ |
Alexandrite |
|
| 9 |
This stone will scratch previous stones |
Ruby Sapphire |
| 10 |
This stone will scratch previous stones. Top of the line tools like saws and drill-bits are often diamond-tipped. It will cut through most things. |
Diamond |
Pronounced: moe-z
Function: Noun
Etymology: German mineralogist
Friedrich Mohs, died 1839
Date: 1879
Function: Noun
Etymology: German mineralogist
Friedrich Mohs, died 1839
Date: 1879
Why is it important to know how hard your gemstones are? If you wear hard and a soft stones side by
side and they have a lot of contact, the harder one can scratch the softer one! To prevent abrasion, stay
within the same range or create a seed bead buffer. If you are using fiber to string your gemstones, try
knotting in-between.
side and they have a lot of contact, the harder one can scratch the softer one! To prevent abrasion, stay
within the same range or create a seed bead buffer. If you are using fiber to string your gemstones, try
knotting in-between.
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