Identification tests for physical and chemical properties

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					-Identification: tests for physical and chemical properties-
 Hardness- how easy it is to scratch (not how easy it breaks)
      Mohs Scale: arranged from 1 (talc) to 10 (diamond)
          glass plate test (5.5) if it scratches plate it’s hard

 Cleavage/fracture: if it breaks smoothly along at least one
    plane it has cleavage, irregular and curved breaks indicate
    fracture
           ex. Halite  cube

 Specific gravity/Density: density compared to water
          ex. Galena  very dense

 Streak: color of powder when rubbed on a porcelain plate
          ex. Magnetite  red

 Luster: how it reflects light (metallic vs. nonmetallic)
          ex. Pyrite  metallic

 Color: sometimes obvious but minerals often have impurities
        that change color
          ex. Sulfur  yellow

 Other properties:
 Texture (greasy Graphite)
 Crystal shape (microscopic)
 Reaction with acids (Calcite bubbles)
 Magnetism (magnetite)
 Double refraction (calcite blurs writing)
 Smell (Sulfur)
 Taste (salty Halite)
 Fluorescent (Fluorite)