Mineral resources 1

Minerals:
Building Blocks of
Rocks
~Chapter 5~
^_^


Minerals: the building
blocks of rocks
Definition of a mineral
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Natural
Inorganic
Solid
Possess an orderly internal structure of
atoms
• Have a definite chemical composition


Composition and
structure of minerals
Atoms
• Smallest particles of matter

• Elements
• Basic building blocks of minerals
• Over 100 are known

Periodic table of the Elements


How atoms are
constructed
Nucleus – central part of an atom that
contains
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Protons – positive electrical charges
Neutrons – neutral electrical charges
Have all the characteristics of an elements

Energy levels, or shells
• Surround nucleus
• Contain electrons – negative electrical
charges


Simplified view of the atom


How atoms are
constructed
Atomic number is the number of
protons in an atom's nucleus

Bonding of atoms
• Forms a compound with two or more
elements
• Ions are atoms that gain or lose electrons

Isotopes
• Have varying number of neutrons


How atoms are
constructed
Isotopes
• Have different mass numbers – the sum of
the neutrons plus protons
• Many isotopes are radioactive and emit
energy and particles


Minerals
 Physical properties of minerals
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Crystal form

Luster
Color
Streak
Hardness
Cleavage
Fracture
Other properties (taste, smell, elasticity, malleability, feel,
magnetism, double refraction)


Crystal Form


Luster


Cleavage


Streak


Hardness


Cleavage


Fracture

Other PropertiesCrystal Form


The mineral quartz often
exhibits good crystal form


Pyrite (fool’s gold)
displays metallic luster



Three examples of perfect
cleavage – fluorite, halite,
and calcite


Conchoidal fracture


Minerals
Physical properties of minerals
• Other properties
• Feel
• Magnetism
• Double Refraction
• Reaction to hydrochloric acid

Minerals
 A few dozen minerals are called the rockforming minerals
• The eight elements that compose most rockforming minerals are oxygen (O), silicon (Si),
aluminum (Al), iron (Fe), calcium (Ca), sodium
(Na), potassium (K), and magnesium (Mg)
• Most abundant atoms in Earth's crust:
• Oxygen (46.6% by weight)
• S ilicon (27.7% by weight)