Transcript Minerals The basic building blocks of Earth

Minerals
The Basic Building Blocks of Earth!
Minerals Video
Minerals…
The BIG Idea!
• Minerals are all around us.
• A mineral is identified by its
properties.
• Minerals are valuable resources.
How many different types of minerals are
there?
• Thousands!
• Most are rare-only about 100 occurring in
abundance. Of those 100 minerals, 15-30
make up the common rock-forming
minerals and some of the remainder have
some economic value.
Galena is a mineral used to make paints
Minerals are everywhere and used daily…
• Common salt is made from
a mineral known as Halite.
• Pots and pans are
made from metal –
stainless steel, cast
iron, copper or
aluminum. All of
these come from
minerals.
Did you know…
• Pencils contain
a mineral called
graphite.
• Toothpaste is
made with a
mineral
Fluorite.
Give me light…
• When you switch on a light,
electricity flows through
copper wires and into a
filament made of tungsten
(which comes from a mineral
called wolframite).
• The filament glows and
shines through a light bulb
of glass (made from
quartz)….Mineral teamwork!
What are the five
characteristics of Minerals?
• Forms in nature (by processes that
do not involve living things).
• Is a solid.
• Has a definite chemical makeup.
• Has a 3-D crystal structure.
• They are inorganic
Minerals are solids…
• They are solids, not liquids or gases, such
as water and air.
• Solids have a definite volume and a rigid
shape.
• Oxygen occurs naturally…
• Is it a mineral?
NO…it is a gas
• An ice cube is a solid form of water and
may occur naturally…Is it a mineral?
NO! (no definite 3-D
shape.)
Minerals have a definite chemical make
up…
• Each mineral has a definite chemical composition each one is made of a particular mix of chemical
elements.
• A mineral’s atoms are arranged in a definite
pattern repeated over and over again.
• Most minerals are compounds (more than one
element)
• EXCEPT for two special minerals:
GOLD and COPPER they are made
of just one element.
Minerals have a geometric or crystal
structure…
• Each mineral has its own type of crystal
structure.
• A solid in which the atoms are arranged in
an orderly, repeating three dimensional
pattern.
• Crystal groups are named by their shapes.
Crystal Patterns
• There are six
major crystal
systems.
• Crystals can form
from magma…
• When magma cools
rapidly, the
crystals that form
will be small.
• When magma cools
slowly, the crystals
that form are
generally large.
Minerals form in nature…
• Minerals must occur naturally. This means
they are not made by humans. Substances
such as steel and cement would not be
considered minerals.
For example…
Talc is formed deep in the Earth.
…Talc is used in cosmetics and baby powders.
This is what the mineral talc looks like!
Minerals are Inorganic
• Living things can produce minerals within
them like human beings produce calcite in
their teeth and bones.
• Seashells are high in calcite.
Minerals are grouped and classified based on
their chemical makeup
1) Silicates (silicon + oxygen)…
most common. The silicates
make up 90% of the rocks in
Earth’s crust. Quartz and Mica
are examples.
2) Carbonates (carbon +
oxygen)…second most common.
Calcite is an example.
Quartz
Mica
Calcite
How are minerals identified?
1. Color
1. Color
2. Streak
3. Luster
4. Cleavage
5. Fracture
6. Hardness
Mineral Properties...Color/Appearance
Color and appearance are two obvious
clues that can be used to identify
minerals. Color is one of the least
reliable properties because a mineral
may have a variety of colors.
Mineral properties...Streak
• When a mineral is
rubbed across a
piece of tile, a
streak or powder is
left behind.
• Streak is the color
of a mineral when it
is in a powdered
form.
Mineral properties...Luster
• The way a mineral
reflects light is known as
luster.
• Luster can be
•
metallic (like metal)
•
nonmetallic (dull,
pearly, silky, and glassy).
Mineral properties...Cleavage
• Minerals that break along smooth,
flat surfaces.
• The bonds of the crystal structure are
weaker in the directions in which the
mineral breaks.
Calcite has
cleavage.
Mineral properties...Fracture
• Minerals that break with uneven,
rough, or jagged.
• When a mineral fractures, the bonds
that join the atoms are equal in
strength.
Sulfur
Mineral properties ...Hardness
A mineral’s
hardness is its
resistance to
being
scratched.
Harder
minerals have
stronger
bonds.
Other Properties…
• Light forms two
separate rays when it
passes through calcite,
Some minerals…
causing you to see a
double image.
• Have a magnetic
quality, such as
magnetite.
• React with a weak
acid (bubble/fizz).
• Glow with a black
light: fluoresce
Are minerals and rocks the same?
No!
• Rocks share two characteristics with
minerals…
They are solids
Form naturally
• Rocks contain one or more minerals
within them.
Can you remember?
Minerals that contain silicon and oxygen
are __________.
A. magma
B. opals
C. silicates
D. solutions
The answer is C. Silicates contain
silicon and oxygen and usually one or
more other elements.
Can you remember?
Which of these is a characteristic of
minerals?
A. solid
B. formed by life processes
C. indefinite chemical composition
D. organic substances
The answer is A. Minerals are solids.
Only a solid can be a mineral, but not
all solids are minerals.
Can you remember?
Minerals that break easily along smooth,
flat surfaces have __________.
A. cleavage
B. fracture
C. luster
D. Streak
The answer is A. Cleavage is determined
partly by the arrangement of the mineral’s
atoms. Minerals that break with uneven
surfaces have fracture.
Can you remember?
Minerals that break into irregular, jagged
pieces, have __________.
A. cleavage
B. fracture
C. luster
D. streak
The answer is B. Minerals that break with
uneven surfaces have fracture.