Transcript Minerals of the Earth`s Crust

Minerals
Minerals
• Minerals are substances that meet five
requirements:
• naturally occurring
• inorganic
• solid
• definite chemical composition
• ordered internal structure
Mineral Characteristics
(The following questions can help determine if a
substance is a mineral or not.)
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Is it formed naturally?
Is it nonliving or inorganic?
Is it a solid?
Does it have a definite chemical composition?
Does it have an ordered internal structure?
• "Naturally occurring" means that
people did not make it. Steel is not a
mineral because it is an alloy
produced by people.
• "Inorganic" means that the substance is not
made by an organism. Wood and pearls are
made by organisms and thus are not
minerals.
• "Solid" means that it is not a liquid or a gas
at standard temperature and pressure.
• "Definite chemical composition" means that
all occurrences of that mineral have a
chemical composition that varies within a
specific limited range. For example: the
mineral halite has a chemical composition
of NaCl. It is made up of an equal number
of atoms of sodium and chlorine.
• "Ordered internal structure" means that the
atoms in a mineral are arranged in a
systematic and repeating pattern. Halite is
composed of an equal ratio of sodium and
chlorine atoms arranged in a cubic pattern.
• Crystals are solid,
geometric forms of
minerals produced by a
repeating pattern of atoms.
• All minerals are grouped
into classes according to
the kinds of crystal the
form.
Types of Minerals
• Minerals are divided into two
groups based on the elements
they are composed of. The
two groups are Silicates and
Non-Silicates.
Mica
Silicates
• Silicates contain the two
most common elements in
the Earth’s crust, silicon &
Feldspar
oxygen.
• Silicates make up 90% of the
Earth’s crust.
• Examples are: Feldspar,
Mica, & Quartz.
Quartz
Non-Silicates
• Non-silicates do not contain both Silicon and
Oxygen.
• Examples are: calcite, galena,pyrite, gypsum,
halite
Value of Minerals
• Ore is the term used
describe mineral deposits
that are large enough to be
mined for profit.
• Ores vary in value and so
do gems. Gems are rare
and attractive.
• After minerals are mined
the land has to be reclaimed
or put back to it’s original
state.
The Hope Diamond
Ore mine pit
Mining
• Surface mining recovers minerals at or near
the surface. Example: Strip Mining or
Open Pit Mining
• Deep Mining far below Earth’s surface.
Deep mining tunnels can be horizontal or
vertical, depending on where they are
located.