Mineralogical hardness: group 6

Hardness ranges on scale from 1 to 10 and depends upno the ability of a material to scratch another.

image showing Mineralogical hardness: group 6 periodic periodicity for group 6 chemical elements


Moh scale


The scale is roughly logarithmic, that is, a material with a hardness of 8 is roughly 10 times as hard as another material whose hardness is 7, which in turn is 10 times as hard as a material whose hardness is 6, and so on. The minerals chosen by Moh for this scale are:

  • 10: diamond
  • 9: corundum
  • 8: topaz
  • 7: quartz
  • 6: orthoclase
  • 5: apatite
  • 4: fluorite
  • 3: calcite
  • 2: gypsum
  • 1: talc

Literature sources

  1. G.V. Samsonov (Ed.) in Handbook of the physicochemical properties of the elements, IFI-Plenum, New York, USA, 1968.

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