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EESC 1101: Chemistry and Minerals
Characteristics of Minerals
Introduction to
Minerals
and their Properties
• NATURALLY OCCURRING
• SOLID
• INORGANIC
• SPECIFIC CHEMICAL COMPOSITION
• SPECIFIC ATOMIC ARRANGEMENT
Characteristics of Mineraloids
Examples of Mineraloids
Amber
Opal
• NATURALLY OCCURRING
• SOLID
• INORGANIC
Volcanic Glass
Coal
• VARIABLE CHEMICAL COMPOSITION
• RANDOM ATOMIC ARRANGEMENT
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EESC 1101: Chemistry and Minerals
Mineral Classes
• Minerals involve bonds between cations and
anions (metals and non-metals)
• Only a few elements form common anions
(C, N, O, P, S, Cl, F)
Mineral Properties
• Specific Composition
– Color
– Density
– Magnetism
• Minerals classified based on anions (non-metals)
• Specific Structure
– Shape
– Breakage
Minerals Are Chemical Compounds
• Defined chemically
• Classified chemically
• Properties based on
chemistry
Generalized Atomic Structure
• Nucleus houses massive
particles (protons and neutrons)
– # Protons = Atomic Number
– # Protons + Neutrons = Atomic Mass
– Responsible for mass and density
• Electrons in orbitals surrounding
nucleus
– # Electrons = # Protons
– Responsible for bonding
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EESC 1101: Chemistry and Minerals
Ions
Metals: Form Positive Ions (Cations)
• Ions: Electrically charged particles due to gain or
loss of electrons
– Cations: positively charged
– Anions: negatively charged
• Metals: readily form cations
• Non-Metals: readily form anions
Non-Metals:
Form Negative Ions (Anions)
Electron Orbitals
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EESC 1101: Chemistry and Minerals
Alkali
Metals
Alkali Earth Transition
Metals
Metals
Other Metals
Absorption Results in Color
Absorption and Emission of Light
Non-Metals
Halogens
(A Familiar Example from Biology)
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EESC 1101: Chemistry and Minerals
Noble Gases
Electronegativity: measure of an atom’s
ability to attract electrons in a chemical bond
Ionic Bonds
• Electron transfer to atom
with higher electronegativity
– Metal to non-metal
• Results in charged ions
• Oppositely charged ions
attract
– Form weak bond
Ionic Bonds
• Ions not “attached”
– Bonds are relatively
weak
– Soft minerals
• Ions attracted by other
charged particles
– Soluble in water
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EESC 1101: Chemistry and Minerals
Ionic Bonds
and Solubility
Ionic Bonds
and Solubility
OH+
H+
OH+
Cl-
H+
Cl-
H+
Na+
H+
O-
O-
H+
H+
Cl-
Na+
Na+
Cl-
H+
H+
O-
O-
H+
H+
Na+
H+
OClH+
Common Ionic Minerals
• Halite (NaCl): Halide
Table Salt, De-Icer
• Calcite (CaCO3): Carbonate
Chalk, Plaster, Toothpaste,
Antacids
OH+
H+
Covalent Bonds
• Approximately equal
electronegativity…
– share one or more
electrons
• Merging of electron clouds
– Forms strong bond
– Hard minerals
• Gypsum (CaSO4•H2O): Sulfate
Drywall, Cement, Plaster
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EESC 1101: Chemistry and Minerals
Metallic Bonds
Common Metallic Minerals
• Little/no difference in
electronegativity in metals
– Delocalized sharing of
free electrons
• Copper (Cu)
• One continuous electron
cloud
– Soft, malleable
– Conductive
• Silver (Ag)
Ore
Ore
• Gold (Au )
Ore
Van der Waal’s “Bonds”
• Imbalance in the
distribution of electrons
(dipole)
• Fleeting and fluctuating
weak attractions
– Soft minerals
– Low melting point
– Allows for the basal
cleavage in micas
Common Van der Waals Minerals
• Talc (Mg3Si4O10(OH)2 ):
Silicate
Baby Powder, Paint, Paper
• Graphite (C ): Element
Pencil Lead, Dry Lubricant
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