I. MINERALS

A. Definition:
  1. Naturally occurring
  2. Inorganic
  3. Solid
  4. Crystalline
    1. specific chemical composition
    2. regular, repeating atomic arrangement
B. Chemical Composition - specific ratio of chemical elements
  1. Atoms
    1. components
    2. structure
  2. Common elements in rocks:

    3. Si, Al, O, Ca, Mg, Fe, Na, K , C
C. Crystal structure - regular repeating atomic arrangement
  1. silicate structure (Fig. 9.8, 9.9, 9.11) - SiO4 tetrahedron
    1. isolated tetrahedra
    2. single chain
    3. double chain
    4. sheet
    5. 3-D framework
  2. silicate minerals (Table 9.2)
    1. isolated tetrahedra -olivine (Fe, Mg)
    2. single chain - pyroxene (Fe, Mg)
    3. double chain - amphibole (Fe, Mg, Ca)
    4. sheet - mica; biotite (Fe, Mg) or muscovite (K)
    5. 3-D framework - Feldspar (Ca, NA, K); Quartz (SiO2)
  3. Non-silicate minerals
    1. calcite (CaCO3)
    2. halite (NaCl)
    3. gypsum (CaSO4. 2H2O)
D. Physical properties
  1. luster
  2. color
  3. crystal shape
  4. cleavage
  5. fracture
  6. hardness
  7. specific gravity
  8. other (fizz, magnetism, double refraction...)
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