Physical properties of Minerals

• Streak is the color of a mineral in its powdered form.
  Luster is used to describe how light is reflected from the surface of a mineral.
  Crystal form is the visible expression of a mineral’s internal arrangement of atoms.
  Hardness is a measure of the resistance of a mineral to being scratched.
  Mohs scale consists of 10 minerals arranged from 10 (hardest) to 1 (softest).
  Cleavgea is the tendency of a mineral to cleave, or break, along flat, even surfaces.