Hardness,in mineralogy,is a measure of 'scratchability'; a material of a given hardness will scratch a material that is not as hard. More than a century ago,mineralogist Friedrich Mohs devised a hardness scale for minerals,called the Mohs scale. A mineral of hardness 7,such as quartz,will easily scratch a softer mineral,such as calcite (hardness 3). In this photo,the calcite specimen is a banded 'onyx'. On the Mohs scale,talc is number 1 and diamond is number 10 | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Arem, Joel |
Taille de l’image : | 3780 px × 2550 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : |
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