Transcript Minerals Powerpoint with notes

EQ: What is a mineral?
Standard: S6E5.b
Investigate the contribution
of minerals to rock
composition.
EQ: What is a mineral?
• What is a crystal, and
what determines a
crystal’s shape?
• Describe the two
major groups of
minerals.
• What is a native
element?
Mineral Structure
• A mineral is a naturally formed, inorganic
solid that has a crystal structure and a
definite chemical composition.
• Minerals may be either elements or compounds.
• Elements are pure substances that cannot be
broken down into simpler substances by
ordinary means.
• A compound is a substance made of two or
more different elements that have been joined
together by a chemical bond.
5 Characteristics of a Mineral
• Naturally Formed- must form naturally
• Inorganic- cannot arise from materials that
were once part of a living thing
• Solid- always solid, with a definite volume
and a definite shape
• Crystalline Structure- particles must line up
in a pattern that repeats over and over again
• Definite Chemical Composition- always
contains certain elements in definite
proportions. NaCl (salt)
Mineral Structure
• A few minerals, such as gold and silver,
are composed of only one element.
• A mineral that is composed of only one
element is called a native element.
• Native elements are used in
communications and electronics
equipment.
Crystals
• A crystal is a solid whose atoms, ions, or
molecules are arranged in a definite pattern.
• Crystals are solid, geometric forms produced
by a repeating pattern of atoms or molecules
that are present throughout the material.
• A crystal’s shape is determined by the
arrangement of the atoms or molecules within
the crystal.
• All minerals can be grouped into crystal
glasses according to the kinds of crystals
they form.
Crystalline Structure of a Mineral
Two Groups of Minerals
• Minerals are divided into two groups based on
their chemical composition.
• Silicate minerals are minerals that contain a
combination of the elements silicon and oxygen
(quartz, feldspar, mica).
• Silicate minerals make up over 90% of the
Earth’s crust.
• Nonsilicate minerals are minerals that do not
contain a combination of the elements silicon
and oxygen ( copper, calcite, fluorite, corundum,
gypsum, galena).
Common Silicate Minerals
Classes of Nonsilicate Minerals
Quick Check
Which of the following is NOT a
characteristic of a mineral?
a.
b.
c.
d.
It is formed in nature.
It is a living material.
It has a crystalline structure.
It is a solid.
Quick Check
Which of the following properties of minerals
does Mohs scale measure?
a.
b.
c.
d.
luster
density
hardness
streak
Quick Check
• 3. Pure substances cannot be broken
down into simpler substances by ordinary
chemical means are called
a. molecules.
b. compounds.
c. crystals.
d. elements.
Quick Check
• 4. Which of the following properties is
considered a special property that applies
to only a few minerals?
a. luster
b. taste
c. hardness
d. density
Quick Check
• 5. Which of the following substances is a
mineral?
a. fluorite, which is a crystalline solid with the
chemical formula CaF2
b. coal, which forms from the remains of living
things.
c. obsidian, which is a volcanic glass and is not
crystalline.
d. brass, which is a metal that is made by
humans.
EQ: How are minerals identified?
• How are minerals
identified?
• What is the Mohs
hardness scale?
• What is the major
difference between an
element and a
compound?
Properties of Minerals
• A mineral is a naturally formed, inorganic solid
that has a crystal structure and a definite
chemical composition.
• Each mineral has its own set of specific physical
properties that can be used to identify it
(hardness, color, streak, luster, density, crystal
system, cleavage, and fracture).
• An element is a substance composed of a single
kind of atom.
• A compound is two or more elements combined
so that the elements no longer have their original
distinct properties.
Identifying Minerals
• Hardness- Mohs hardness scale ranks ten
minerals from softest to hardest.
• Color- Because of factors, such as impurities,
used only to identify a few minerals
• Streak- the color of a mineral in its powdered form
• Luster- how a mineral reflects light from its
surface
• Density- the ratio of the mass to the volume of
a substance
• Crystal Systems- six groups of structures based
on the number and angle of the crystal faces
• Cleavage – splitting along smooth, flat surface
• Fracture- breaking apart along curved or irregular
surfaces
Mohs Hardness Scale
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Talc
Gypsum
Calcite
Fluorite
Apatite
Orthoclase
Quartz
Topaz
Corundum
Diamond
1
2
3
4
5
6
7
8
9
10
Softest known mineral
fingernail can scratch it
scratched by copper penny
easily scratched by steel knife
can be scratched by steel knife
can scratch window glass
can scratch steel
can scratch quartz
can scratch topaz
hardest known mineral
Moh’s Hardness Scale
Special Properties
• Some properties are particular to only a few
types of minerals:
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Fluorescence – glow under ultraviolet light
Chemical Reactions – reacts to an acid
Magnetism – natural magnets that attract iron.
Taste – ex. Halite has a salty taste
Optical Properties – some can cause a double
image
• Radioactivity – minerals that contain radium or
uranium
Special Properties of Some Minerals
Quick Check
•
1. What are the two major groups of
minerals?
a.
b.
c.
d.
metallic and nonmetallic
native elements and carbonates
silicates and nonsilicates
quartz and mica
Quick Check
•
2. Silicate minerals contain a
combination of the elements
a.
b.
c.
d.
Sulfur and oxygen.
Carbon and oxygen.
Iron and oxygen.
Silicon and oxygen.
Quick Check
•
3. Which of the following is a nonsilicate
mineral?
a.
b.
c.
d.
orthoclase, KASi3O8
Talc, Mg3Si4O10(OH)2
Almandine, Fe3Al2(SiO4)3
Magnetite, Fe3O4
The Formation, Mining, and Use of
Minerals (p.74)
• Where can you find
minerals?
• What is an ore?
• Compare surface and
subsurface mining.
• What is reclamation?
• What are some examples
of minerals and their
uses?
The Formation of Minerals
• Minerals form in a variety of environments
in Earth’s crust.
• Each of these environments has a
different set of physical and chemical
conditions.
• The environment in which a mineral forms
determines the mineral’s properties.
• Environments in which minerals form may
be on or near Earth’s surface or deep
beneath Earth’s surface.
Formation Environments
The Environments
Evaporating Salt Water
• When a body of salt water dries up,
minerals are left behind.
-(gypsum, halite)
Metamorphic Rocks
• When changes in temperature, pressure,
or chemical make-up changes a rock,
metamorphism takes place.
• -(calcite, garnet, graphite, hematite,
magnetite, mica, and talc)
The Environments
Limestones
• Rocks formed when the surface water and
ground water carry dissolved materials to lakes
and seas where they crystallize on the bottom.
-(Calcite, dolomite)
Hot-Water Solutions
• Environment in which groundwater works its way
downward and is heated. Groundwater works its
way downward and is heated by magma and
then reacts with minerals.
-(gold, copper, sulfur, pyrite, galena)
The Environments
Pegmatites
• Teardrop-shaped bodies with large crystals, such
as gemstones, that form when magma moves
upward.
-(many gemstones, such as topaz, tourmaline)
Plutons
• As magma rises upward through the crust, it
sometimes stops moving before it reaches the
surface and cools slowly, forming millions of
mineral crystals. The entire magma body
solidifies to form a pluton.
– Mica, feldspar, magnetite, quartz
Mining
• An ore is the natural material large enough and
pure enough to be mined for profit.
• Rocks and minerals are removed from the
ground by one of two methods-surface mining
and subsurface mining.
• Surface mining is used to remove mineral
deposits on or near the Earth’s surface.
- open pits
- surface coal mines (open-pit)
- quarries
Mining
• Subsurface mining is used when mineral
deposits are located too deep within Earth to be
surface mined.
• Mine reclamation is the process by which land
used for mining is returned to its original state or
better.
• Has been required by law since the mid-1970’s.
• To reduce the effects of mining, reduce our
need for minerals, reuse, and recycle.
Surface Mining
• This quarry in
northwest
Georgia is an
open pit used
to mine
granite.
Subsurface Mining
• Subsurface
mining is the
removal of
minerals from
DEEP within
the Earth.
Passageways
must be dug
underground to
reach the ore.
The Use of Minerals
• Some minerals are of major economic and
industrial importance.
• Metallic minerals have shiny surfaces, do
not let light pass through them, and are
good conductors of heat and electricity.
• Nonmetallic minerals have shiny or dull
surfaces, may let light pass through them,
and are good insulators of electricity.
The Use of Minerals
• Gemstones are highly valuable minerals
because of their beauty and rarity rather
than their usefulness.
• Color is the most important characteristic
of a gemstone.
• The more attractive the color is, the more
valuable the gem is.
• Mass of a gem is expressed in a unit
known as a carat.
• One carat is equal to 200 mg.
Gemstones
The Cullinan
Diamond, at
the center of
the scepter, is
part of the
largest
diamond ever
found.
Common Uses of Minerals
Mineral
Uses
Copper
Electrical wires, plumbing, coins
Diamond
Jewelry, cutting tools, drill bits
Galena
Batteries, ammunition
Gibbsite
Cans, foil, appliances, utensils
Gold
Jewelry, computers, spacecraft, dentistry
Gypsum
Wallboards, plaster, cement
Halite
Nutrition, highway de-icer, water softener
Quartz
Glass, computer chips
Silver
Jewelry, photography, electronic products
Sphalerite
Jet aircraft, spacecraft, paints
Some Material Used in the Parts of a
Bike
Quick Check
• In a mineral, the particles line up in a
repeating pattern to form
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A.
B.
C.
D.
an element
a crystal
a mixture
a compound
Quick Check
• The term that describes how a mineral
reflects light is its __________.
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A. luster.
B. streak
C. color.
D. weight.
Quick Check
• One characteristic that a substance must
have to be considered a mineral is _____.
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A. to be living.
B. to be small.
C. to a liquid.
D. to be a solid.
Quick check
• A compound is two or more ________
chemically combined.
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A. atoms
B. minerals
C. elements
D. protons
Quick Check
• An element is a substance composed of a
single kind of __________.
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A. compound.
B. atom.
C. mineral.
D. Mohs hardness scale.
Quick Check
•
The groupings silicate and nonsilicate
minerals are based on
a.
b.
c.
d.
Organic content.
Gas and liquid state
Chemical composition.
Color.
Quick Check
•
Nonsilicate minerals
a.
b.
c.
d.
Do not contain oxygen.
Include native elements.
All have a nonmetallic luster.
Are all rare substances.
Quick Check
Which of the following is NOT a class of
nonsilicate minerals?
a.
b.
c.
d.
oxides
Micas
carbonates
native elements
Quick Check
What is a mineral deposit that is large and
pure enough to be mined called?
a.
b.
c.
d.
gemstone
ore
pluton
pegmatite
Quick Check
Halides form when fluorine, chlorine, or
bromine combine with any of the
following elements EXCEPT
a.
b.
c.
d.
sodium.
potassium.
calcium.
oxygen.
Quick Check
•
What is the name for nonmetallic
minerals that are valued for their beauty
and rarity rather than their usefulness?
a.
b.
c.
d.
plutons
gemstones
ores
pegmaites
Quick Check
•
What kinds of mines are open pit and
quarry mines?
a.
b.
c.
d.
shaft mines
slope mines
surface mines
subsurface mines
Quick Check
• Which rocks are exposed to more wind,
rain, and ice?
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A. rocks at a lower elevation
B. rocks at a higher elevation
C. rocks in streams
D. rocks in warm, humid climate