Chapter 2
Chapter 2 Minerals
Reading: 2.1-2.6
Relationships to Earth Systems
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Biosphere
Hydrosphere
Atmosphere
Lithosphere
1) Calcite Limestone,
2) Halite,
3) Clay minerals
2.1 What is a Mineral?
• A mineral is a naturally occurring, inorganic
solid, with a definite chemical composition
and crystalline structure.
Is Ice a Mineral?
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According to our definition?
Naturally occurring?
Inorganic? Solid?
Chemical composition ?
Crystalline structure?
2.2 Chemical Composition
• First lets go to Atoms !
• All matter is made of Atoms.
• Every speck of Gas, liquid, or
Solid surrounding you is a mix
of millions of Atoms.
Atoms and Elements
“The Big 8” Most Abundant Elements
in Earth Crust
Charging Particles: Ions
Positive Charge +
Cation
(1-8)
Negative Charge –
Anion
(1-4)
Other Bonds
• Covalent Bond
Between 2 Nonmetals neither one donates
or gives up an electron, They simply Share in
outer orbital shell forming Covalent bond
• Metallic Bond
very few electrons in the outer most
electron shells. Instead of donating or
sharing these electrons are released
from the orbital shell and available for a
nearby cluster of atoms to use.
“floting in a sea of Electrons”
Formulating Compounds
• SiO2
• (Mg, Fe)2SiO4
2.3 Crystalline Nature of Minerals
• A crystal is any substance whose atoms are
arrange in a regular, periodically repeated
pattern.
• When atoms combine to form minerals they
so in organized way that forms a geometric
pattern called crystal.
Crystals
Minerals and Rocks
• Room 222 ( Geology Building).
• Geology Building lobby
• Museum ?
Physical Properties of Minerals
 1 Crystal habit (shape)
 2) Cleavage & fracture
 3) Hardness
 4) Specific gravity
 5) Color
 6) Streak
 7) Luster
 Others (Taste, Reaction to Acid, magnetism. )
Crystal Habit
Quartz: elongated crystals
Quartz: no characteristic shape
Cleavage & Fracture
Mohs Mineral Hardness Scale
Specific Gravity
Quartz 2.7
Au 19
Color
Luster
Other
Mineral Classes
Silicates
O
Si
O
O
O
Carbonates
2.6 Commercially Important Minerals
Important Minerals
2.7 Harmful and Dangerous Roks and
Minerals
• Asbestos.
• Feldspar  Quartz
Next Class
• Rocks