Friedrich Mohs
image goes here
Friedrich Mohs was an Austrian scientist. He worked out a scale for the hardness of minerals, in 1812. The scale goes from 1 to 10. Each rock in the scale can only scratch other rocks that come below it. Diamond is at the top of the scale, with a rating of 10, which means it can scratch anything. Talc is the softest, with a rating of 1. Mohs based his hardness scale on the following ten types of rock:
  1. talc
  2. gypsum
  3. calcite
  4. fluorite
  5. apatite
  6. orthoclase
  7. quartz
  8. topaz
  9. corundum
  10. diamond