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Author Topic: Mohs Scale of Hardness  (Read 117 times)

Andrew

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Mohs Scale of Hardness
« on: February 19, 2019, 01:57:34 pm »

Mohs Scale of Hardness

The Mohs Scale of Hardness describes the relative hardness of some common minerals -- based on their ability to "scratch" one another.

The unit increments are based on the hardness of (arbitrarily selected) minerals in Mohs' original list. That means they are not linear with respect to absolute hardness. For instance, diamond is 16 times harder than quartz, and the difference between the two in Mohs scale is 3 units. But, the difference between feldspar and quartz is only about 40% in terms of absolute hardness, while they differ by a whole Mohs unit.



Here are the values found on the original Mohs (1812) scale shown alongside "absolute" hardness equivalents.

Mohs HardnessMineralAbsolute Hardness
1Talc1
2Gypsum3
3Calcite9
4Fluorite21
5Apatite48
6Feldspar72
7Quartz100
8Topaz200
9Corundum400
10Diamond1600

Moh Hardness of some common items:
ItemMohs Hardness
Fingernail2.5
Paper clip4.5
Steel knife blade5 - 6.5
Copper penny3
Glass6 - 7
Hardened steel file7+


References:
http://www.amfed.org/t_mohs.htm
« Last Edit: February 19, 2019, 03:27:51 pm by Andrew »
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AltonErurf

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Ocoeoc cpoeca oee Moce
« Reply #1 on: May 04, 2019, 02:06:55 pm »

Cpoeco oee a eppop Moc ee eaoe oeco aco, oope o a,     http://mirsmi24.ru
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