GLY 4200C

Mineralogy and Crystal Chemistry

Word List for Midterm 2, Fall 2012

The second midterm will be given on Wednesday, October 24, 2012 at 9:00 a.m. It will cover the following pages of the assigned reading:

Chapter 5, pages 90-108

Chapter 6

Chapter 7

Chapter 9, 182-208

Chapter 10

Magnetism

In addition, the lecture material will be tested, as will homework exercises #3 and 4.

Composition of the Earth

Crust

Major elements

Minor and trace elements

Mantle

Upper

Transition zone

Lower

Core

Outer

Inner

Abundance measurements

Weight percent

Atom percent

                   Volume percent 

Ores

Effect of pressure and temperature

Mineral Composition Variability

Victor Goldschmidt

Goldschmidt’s Rules (know how to apply)

Size

Charge

Other factors affecting solid solution

Temperature

Pressure

Availability of ions

Spin State - low versus high

Crystalline solution, aka solid solution

End members

Substitutional

Chemical defects

Omission

Vacancy

Interstitial

Defects -Physical

Schottky

Frankel

Stacking

Grain boundary

Polymorphous minerals

Polytypous minerals

Pseudomorphic minerals

Stable vs. metastable

Mineraloids

Ex-solution

Order-Disorder

Metamict

Glass

Crystallographic Concepts

Atomic arrangement

Unit cell

Auguste Bravais

Bravais Lattice

Lattice requirements

Environment around all lattice points must be identical

Unit cell must fill all space, with not holes

Types of lattice P,I,C,F,R

Axes system

x, y, z

Unit cell vectors

a, b, c

Angles between axes

α (Y-Z), β (X-Z), γ (X-Y)

Crystal Systems - know their properties

Isometric

Tetragonal

Orthorhombic

Hexagonal

Hexagonal

Rhombohedral

Monoclinic

Triclinic

Arrangement of ions

Ions can be arranged around lattice points only in certain ways = point group

         Point Group

One or more particular points in group remains unmoved

Collection of mathematical operations which, taken together, define all possible, nonidentical, symmetry combinations

Internal Order and Symmetry

Symmetry - Proper Operation (not involving displacement) and associated element

Rotation about an axis (know the types of axes)

Reflection across a plane

Inversion through a point, the inversion center

         Definition of symmetry operation

Motif

Identity operation

Combinations of simple operations

Know what symbols mean (i.e., 2/m , 2mmm, 3m , 3/m , etc.)

Ditetragonal dipyramid

Derivative structures - effect of lowering symmetry

Complex symmetry operations (aka improper operations)

Roto-inversion

Roto-reflection

Know symbols

Hermann-Mauguin symbols

Crystal Systems

William Hallowes Miller

Notation

Lattice point specification - no bracket e.g. 100

Miller Index - for a plane (hkl or hkil for hexagonal) - know how to compute

Form {hkl} - collection of planes

                            Closed vs. Open 

Zone [uvw]

Zone Axis - know how to compute

Faces of forms

Isometric System

Hexahedron

Octahedron

Dodecahedron

Tetrahedron

Law of Huay

Law of Bravais

Types of Forms

Pedion

Pinacoid

Dome

Sphenoid

Disphenoid

Prism

Pyramid

Dipyramid

Scalenohedron

Rhombohedron

Forms related to the octahedron

Hexoctahedron

Trigonal trisoctahedron

                            Trapezohedron 

Pyritohedron

Tetrahexahedron

Crystal Growth

Mineral size and weight range

Methods of growth

Crystallization from an aqueous system

Crystallization from a magma

Crystallization from a vapor

Nucleation

Supersaturation

Destuction of nuclei (surface area/volume)

Critical Size

Rate of growth

Vectorial properties

Variation - continuous versus discontinuous

Examples of properties

Crystal intergrowths

Epitaxial

External crystal habit reflecting internal symmetry

Twinning

Twin Operations

Twin reflection

Twin rotation

Twin inversion

Twin Elements

Twin plane

Twin rotation

Twin center

Twin Law

Specification of twin element

Orientation of twin element

Composition surface

Types of twinning

Contact twins

Polysynthetic twin

Cyclic twin

Penetration twin

Origin of twinning

Primary twinning

Growth

Secondary twinning

Transformation

Deformation

Twin Laws associated with different crystal systems

Color in minerals

Sources of color

Selective absorption

Crystal Field transitions

Charge Transfer transitions

Color Center transitions

Dispersion

Idiochromatic

Allochromatic

Electromagnetic radiation

Gamma

X-ray

Ultraviolet

Visible

Infrared

Radar

FM

                   TV

Shortwave

AM

Interaction of light with a surface

Transmitted

Refracted

Absorbed

Reflected

                   Scattered 

Crystal Field Splitting

Octahedral

Tetrahedral

Square Planar

Magnetism

Early observations

Bohr magnetron

Spin and orbit contributions

d and f electrons

Correlation of # of 3d electrons with net magnetic moment

Magnetic susceptibility

Diamagnetic

Paramagnetic

Curie temperature

Ferromagnetic

Antiferromagnetic

Néel temperature

Ferrimagnetic

Magnetic separation

Magnetic remote sensing

         Paleomagnetism

Polarity reversal

Plate movement

Questions comments? mailto:warburto@fau.edu

Last updated: October 11, 2012