Mohs scale

Episode 4 of Mineralogy and Crystallography delves into the Mohs Hardness Scale. This episode builds upon our understanding of mineralogy, crystals, and crystal systems to introduce a crucial tool for mineral identification. We will explore the history and development of the Mohs scale, learn how it is used to determine a mineral's relative hardness, and discuss the limitations and applications of this important concept. This episode will equip you with the knowledge to use the Mohs scale effectively in mineral identification, preparing you for future topics like silicate minerals and mineral cleavage.

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These are the same multiple-choice questions you will see in the Quiz section after you listen to the episode. Use them here to preview or review the answers.

Who developed the Mohs Hardness Scale?

  1. James Hutton
  2. Friedrich Mohs
  3. Charles Darwin
  4. Alfred Wegener
  5. Niels Steno

Which of the following is the hardest mineral on the Mohs scale?

  1. Quartz
  2. Topaz
  3. Diamond
  4. Corundum
  5. Talc

The Mohs scale is a measure of a mineral's:

  1. Color
  2. Density
  3. Hardness
  4. Cleavage
  5. Crystal habit

If mineral A scratches mineral B, which is harder?

  1. Mineral A
  2. Mineral B
  3. They are equal in hardness
  4. Cannot be determined

Which of the following objects has a hardness closest to 5.5 on the Mohs scale?

  1. Fingernail
  2. Copper penny
  3. Window glass
  4. Steel nail
  5. Talc

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