Introduction to Mineralogy
Dr. Tark Hamilton
Lecture 2
Camosun College GEOS 250
Lectures: 9:30-10:20 M T Th F300
Lab: 9:30-12:20 W F300
A Mineral Cornelius S. Hurlbut
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A mineral is a wondrous thing. At least it is to me,
For in its ordered structure lies a world of mystery.
The secrets that it has withheld for countless ages past,
And clung to most tenaciously and being learned at last.
Each year using new techniques or with a new device,
We make our knowledge more complete, our data more precise.
But let us not in trying to solve a mineral mystery,
Forget that minerals are a part of natural history.
Nor in our quest for more detail in probing an unknown,
Forget that every mineral has a beauty of its own.
With progress in technology each year sees new machines,
That try to copy nature by sophisticated means.
But for all these modern methods we cannot yet compete,
With the world of ordered beauty that lies beneath our feet.
Course Objectives
• Solid Earth Materials (specimens), their
structure & chemistry (theory)
• Symmetry Elements & Crystallography of
regular space filling lattices, Crystal
systems, Space groups
• Mineral Classification: Dana & Stuntz,
Groups by anions, elements, structures.
Common silicates & ore minerals
• Optical Mineralogy: theory & petrography
• Mineral formation, crystallization, kinetics
Mineralogy Resources
• The Manual of Mineral Science, (Dana’s Mineralogy)
23rd ed., Case Klein & Barb Dutrow, Wiley 2008
• Mineralogy, 2nd ed. Dexter Perkins, Prentice Hall, 2002
• Minerals and Rocks: Exercises in Crystal and Mineral
Chemistry, Crystallography, X-ray Powder Diffraction,
Mineral and Rock Identification, and Ore Mineralogy
Case Klein
• Minerals in Thin Section, Dexter Perkins and Kevin
Henke, 2nd ed., 2004
• Websites, mineral databases, crystallography, models,
symmetry
WEB RESOURCES
• http://webmineral.com/help/Forms.shtml#isometr
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• http://www.rockhounds.com/rockshop/xtal/part1.
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• http://www.klingereducational.com/
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• http://home.comcast.net/~eswab/ObjectThumbn
ails.html
Webmineral.com
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Mineral name, formula, composition…
Crystal form, symmetry, rotational views
X-ray diffraction 3 biggest peaks
Mineral search by element: Mg, Na, Ti etc.
Environment of formation
Locality
Show a crystal cut-out model:
http://webmineral.com/crystal/Isometric
-Hextetrahedral.shtml
System: Isometric
Class: Hextetrahedral (48 faced)
Herman-Maugin Symbol: 4bar 3 m
Forms: (024), (124)
Minerals
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Solid
Definite composition
Naturally occurring
Usually crystalline, not all well formed
~ Inorganic (some oxalates (C2O4)-2 )
~ Form by inorganic processes (some bio)
Forming rocks: mono-mineralic or poly-
Gas Hydrate Crystal – Type I
TETRAKAIDECAHEDRON: Weaire & Phelan, 1993
Methane hydrates are built from water cages held together by hydrogen bonding. Methane
molecules held within 14 faced coordination structures. Repulsive, symmetric, energetic
methane occupies enough of the sites to hold the structure up and keep it from collapsing
under its own weight and water’s intermolecular forces.
How Mineral Formation Differs from
Synthetic Crystalline Substances
• Geological time spans:
Quickly (seconds) - Hydrothermal to
Slowly – Magmatic crystallization to
Mega-annum – Regional Metamorphism
• High Temperatures (200°C to 1700°C) &
High pressures (102’s–106’s bar)
Specific/unusual compositions (Low fO2)
• Order/Disorder, inclusions, flaws, cooling
Minerals Comprise Rocks
• Sedimentary: Grains - Quartz (ancient, Ga),
Cements: Dolomite, Greigite (diagenetic, ~a)
• Metamorphic: Garnet, Biotite, Quartz, Feldspar
(mountain building recrystallized, 107 a)
• Igneous: Olivine, Pyroxene, Plagioclase,
Magnetite (magma cooling, 100 a - 105 a)
• Meteoritic: Kamacite (Fe>Ni), Taenite (Ni>Fe),
Troilite (FeS), Olivine ((Mg,Fe)2 SiO4), Carbon
(at 4.6 Ga, High-T & Lo-P from Solar nebula)
Dol
Gr
Q
Klein & Dutrow 2008, fig_01_09
Mineral Science:
What Mineralogists Do
• Crystallography: Forms, symmetry, XRD
• Crystal Chemistry: Inorganic, substitution,
kinetics of formation
• Classification: Composition & Structure,
~50 new minerals a year, ~4000 total
• Paragenesis: Geological occurrence,
assemblage, setting, conditions
• Descriptive: Locality, form, habit, colour
Klein & Dutrow, 2008 fig_01_08
History of Technical Mineral Use
• >40,000 BCE Fe2O3 red & MnO(OH) black cave
art & Cu beads
• > 3000 BCE Turquoise, Jade hoarded, collection
& trade
• 2900 BCE Egypt & Bronze Age Greece: Gold
smelting & refining
• 1500 BCE “Refining minerals” Plaster burners,
Charcoal reduction of metal
• 1500 BCE Semitic Chetites, Fe tools
• 1000 BCE India Fe tools, Egypt Hg
• 1300 AD Additional smelting refining
Ancient Mineral Writings & Ideas
• Heiroglyphics ~2900 BCE (Bronze Age),
Au, Ag, Cu-Sn, Ceramics, Enamelwork
• Leucippo 500 BCE Theory of “Atoms”
• Empedocles 430 BCE Earth, Air, Fire, H2O
• Theophrastus 287 BCE “Concerning
Stones”
• Pliny 79 CE Natural History
Cornelius Agricola (1556) De Re Metallica
Mining &
Ore Smelting
Raises, tunnels, ore cars,
Winzes, headframes
(note clearcut – wood fuel)
The Road to Modern Mineralogy
• 1669 Nicolaus Steno: Constant interfacial angles
of quartz from different places
• 1783 Rome d’L’Isle & Carangeot: Goniometer
contact & Law of Constancy of Interfacial Angles
• 1784 Rene de Hauy: Crystals built up from
“integral molecules” (unit cells)
• 1801 Rene de Hauy: Rational Indices for Crystal
Faces
• 1809 Wollaston: Reflection goniometer
The Road to Modern Mineralogy
• 1874 Miller 2 circle goniometer, dihedral angles
• 1889 Federov poles to crystal faces plotted in
stereographic projection (Wulff net) shows
symmetry between faces
• 1914 Von Laue X-ray diffraction of ZnS NP
• 1921 G. Tschermak & F. Becke Polarizing
Microscope
Mineralogy, Alchemy & the Roots of Modern
Chemistry
• 1660 Robert Boyle: Sceptical Chemist
“Elements” used in modern sense
• ~1750 Joseph Proust: Elements combine in
Definite Proportions  Compounds
• ~1800 John Dalton, Wm Higgins Law of definite
proportions (weight ratios)
• 1813 Jons J. Berzelius: Symbols & Atomic
weights for 15 elements/Oxygen
• 1837 J. D. Dana: A System of Mineralogy
• 1870 Dimitri Mendeleyev: Periodic Chart
• 1871 J. L Meyer: Atomic volumes vs wts.
Lifetime Per Capita Mineral Usage
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1.64 X 106 Kg all minerals
361 Kg Pb: batteries, solder
261 Kg Zn: brass, cathodics, chemicals
682 Kg Cu: wiring, alloys
1633 Kg Al: aircraft, cans, foil, lawn chairs
14864 Kg Fe: spoons nails cars ships bldg
12824 Kg NaCl: deicing, detergent, food
562773 Kg: Stone, gravel, sand
Example Mineral Name Origins
• Bytownite (Ab30-10An70-90) Bytown = Ottawa
• Calcite (CaCO3) calx, L. Lime
• Carletonite (KNa4Ca4Si8O18(CO3)4(OH,F) H2O) Carleton
U., Mont St. Hilaire
• Cassiterite (SnO2) kassiteros, Gr. Tin
• Labradorite (Ab50-30An50-70) Labrador
• Monteregianite KCa2AlSi7O17(OH)2·6(H2O) Monteregian
Hills PQ, (Hydrodelhayelite)
• Sperrylite (PtAs2) F. Sperry (discoverer), ON