Another distinguishing feature of minerals is
hardness. This is a measure of the resistance of a mineral to abrasion or scratching.Geologists use a standard hardness scale called the
Mohs scale.It consists of 10 minerals arranged in order from hardest (10 - diamonds) to softest (1 - talc). One determines the hardness of a mineral by rubbing it against a mineral of known hardness.One will scratch the other, unless they have the same hardness.For example, your fingernail has a hardness of 2.5 and can easily scratch gypsum with a hardness of 2.However, you will not be able to scratch a copper penny whose hardness is 3. |
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