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The Mohs scale of hardness indicates
the scratch resistance of various minerals and measures the hardness
of a gemstone on a scale of 1 to 10. This scale was developed
in 1812 by the German mineralogist, Friedrich Mohs.
Stones are tested by scratching
them with known gemstones. If a stone can be scratched by another,
it has a lower number of hardness. Conversely, if a stone cannot
be scratched by another, then the tested stone has a higher number
of hardness.
The minerals used to
identify
the numbers on the Mohs scale are: |
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Common Gemstones
on the Mohs Scale |
| Softest to Hardest |
Mineral |
Gemstone |
Mohs Hardness |
1
2
3
4
5
6
7
8
9
10 |
Talc
Gypsum
Calcite
Fluorite
Apatite
Orthoclase
Quartz
Topaz
Corundum
Diamond |
Agate
Amazonite
Amethyst
Aquamarine
Carnelian
Citrine
Diamond
Emerald
Garnet
Jade
Jasper
Labradorite
Lapis Lazuli
Onyx
Peridot
Quartz
Ruby
Sapphire
Spinel
Topaz
Tourmaline
Turquoise |
7.0 Mohs
6.0 Mohs
7.0 Mohs
8.0 Mohs
7.0 Mohs
7.0 Mohs
10.0 Mohs
8.0 Mohs
6.5 Mohs
6.0 Mohs
7.0 Mohs
6.5 Mohs
6.0 Mohs
7.0 Mohs
7.0 Mohs
7.0 Mohs
9.0 Mohs
9.0 Mohs
8.0 Mohs
8.0 Mohs
7.5 Mohs
5.0 Mohs |
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