Mineralogy and Petrology

  1. Optical Mineralogy
    1. The Petrographic Microscope
      1. Components and Function
        1. Light Source
          1. Illumination Systems
            1. Light Intensity Control
            2. Polarizers
              1. Lower Polarizer
                1. Upper Polarizer (Analyzer)
                  1. Polarization Principles
                  2. Stage
                    1. Rotating Stage
                      1. Centering Mechanisms
                        1. Stage Clips
                        2. Objectives
                          1. Magnification Powers
                            1. Numerical Aperture
                              1. Working Distance
                              2. Eyepiece
                                1. Magnification
                                  1. Crosshairs
                                    1. Focusing Mechanisms
                                  2. Microscope Setup and Alignment
                                    1. Köhler Illumination
                                      1. Centering Procedures
                                        1. Focus Adjustments
                                        2. Plane Polarized Light
                                          1. Single Polarizer Use
                                            1. Vibration Direction
                                            2. Crossed Polarized Light
                                              1. Both Polarizers Engaged
                                                1. Extinction Positions
                                              2. Properties in Plane Polarized Light
                                                1. Color and Pleochroism
                                                  1. Absorption Colors
                                                    1. Pleochroic Minerals
                                                      1. Biotite
                                                        1. Hornblende
                                                          1. Tourmaline
                                                          2. Pleochroic Schemes
                                                            1. Color Notation
                                                              1. Absorption Formulas
                                                            2. Relief
                                                              1. Refractive Index Differences
                                                                1. High Relief
                                                                  1. Strong Boundaries
                                                                    1. Becke Line Movement
                                                                    2. Moderate Relief
                                                                      1. Visible Boundaries
                                                                      2. Low Relief
                                                                        1. Weak Boundaries
                                                                          1. Similar Refractive Indices
                                                                        2. Cleavage
                                                                          1. Observation in Thin Section
                                                                            1. Cleavage Traces
                                                                              1. Spacing and Quality
                                                                              2. Cleavage vs. Fractures
                                                                                1. Crystallographic Orientation
                                                                                2. Crystal Form
                                                                                  1. Euhedral
                                                                                    1. Well-formed Faces
                                                                                      1. Complete Crystal Outline
                                                                                      2. Subhedral
                                                                                        1. Partially Formed Faces
                                                                                          1. Some Crystal Boundaries
                                                                                          2. Anhedral
                                                                                            1. No Crystal Faces
                                                                                              1. Irregular Boundaries
                                                                                            2. Alteration Features
                                                                                              1. Weathering Products
                                                                                                1. Replacement Textures
                                                                                                  1. Inclusion Patterns
                                                                                                2. Properties in Crossed Polarized Light
                                                                                                  1. Isotropy vs. Anisotropy
                                                                                                    1. Isotropic Minerals
                                                                                                      1. Cubic System Minerals
                                                                                                        1. Constant Refractive Index
                                                                                                          1. Remain Dark
                                                                                                          2. Anisotropic Minerals
                                                                                                            1. Non-cubic Minerals
                                                                                                              1. Variable Refractive Indices
                                                                                                                1. Show Interference Colors
                                                                                                              2. Birefringence and Interference Colors
                                                                                                                1. Double Refraction
                                                                                                                  1. Optical Path Differences
                                                                                                                    1. Order of Interference Colors
                                                                                                                      1. First Order Colors
                                                                                                                        1. Second Order Colors
                                                                                                                          1. Higher Order Colors
                                                                                                                          2. Michel-Lévy Chart
                                                                                                                            1. Color-Thickness Relationships
                                                                                                                              1. Birefringence Determination
                                                                                                                            2. Extinction Angle
                                                                                                                              1. Angle Measurement
                                                                                                                                1. Types of Extinction
                                                                                                                                  1. Parallel Extinction
                                                                                                                                    1. Cleavage Parallel to Crosshairs
                                                                                                                                    2. Symmetrical Extinction
                                                                                                                                      1. Symmetric to Crystal Outline
                                                                                                                                      2. Oblique Extinction
                                                                                                                                        1. Inclined to Reference Features
                                                                                                                                          1. Maximum Extinction Angles
                                                                                                                                      3. Twinning
                                                                                                                                        1. Optical Recognition
                                                                                                                                          1. Types of Optical Twinning
                                                                                                                                            1. Simple Twins
                                                                                                                                              1. Multiple Twins
                                                                                                                                                1. Polysynthetic Twins
                                                                                                                                                2. Extinction Patterns
                                                                                                                                                  1. Compositional Differences
                                                                                                                                                3. Uniaxial and Biaxial Minerals
                                                                                                                                                  1. Optic Axis Concepts
                                                                                                                                                    1. Optical Indicatrix
                                                                                                                                                      1. Principal Refractive Indices
                                                                                                                                                      2. Uniaxial Minerals
                                                                                                                                                        1. Single Optic Axis
                                                                                                                                                          1. Ordinary and Extraordinary Rays
                                                                                                                                                            1. Hexagonal and Tetragonal Systems
                                                                                                                                                            2. Biaxial Minerals
                                                                                                                                                              1. Two Optic Axes
                                                                                                                                                                1. Alpha, Beta, Gamma Indices
                                                                                                                                                                  1. Orthorhombic, Monoclinic, Triclinic Systems
                                                                                                                                                                  2. Interference Figures
                                                                                                                                                                    1. Conoscopic Observation
                                                                                                                                                                      1. Uniaxial Figures
                                                                                                                                                                        1. Centered Optic Axis
                                                                                                                                                                          1. Off-Center Figures
                                                                                                                                                                            1. Sign Determination
                                                                                                                                                                            2. Biaxial Figures
                                                                                                                                                                              1. Acute Bisectrix Figures
                                                                                                                                                                                1. Obtuse Bisectrix Figures
                                                                                                                                                                                  1. Optic Normal Figures
                                                                                                                                                                                  2. Accessory Plates
                                                                                                                                                                                    1. Gypsum Plate
                                                                                                                                                                                      1. Mica Plate
                                                                                                                                                                                        1. Quartz Wedge

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                                                                                                                                                                                  4. Physical Properties of Minerals

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                                                                                                                                                                                  6. Systematic Mineralogy