Activator
Rock vs Mineral?
Decide if each object shown better represents a rock or a mineral.
Hold up the rock side or mineral side of your page.
Example:
Rock
Why? It has more than one substance, the
bristles and the handle
Chalk
Mineral
It is only made up of one substance –
the same throughout
Paperclip
Mineral
It is only made of metal, and it looks
the same throughout
Spiral Notebook
Rock
It has more than one substance, the metal,
spiral, and the paper.
White paper
Mineral
It looks the same throughout
and is all paper
Stapler
Rock
It has more than one part. It has staples
and the metal body.
Spoon
Mineral
It is all metal and looks the same
throughout.
Globe
.
Rock
It has metal and plastic
Minerals
Part One
Minerals
Text pgs. 118-126
What are they?
 How do we identify them?

Minerals are…
Formed naturally (occurring)
Minerals are…
Made of materials that were never alive
(inorganic)
Minerals are…
gold nuggets
Solids
Have a definite shape and volume
Minerals have a…
Definite chemical composition
Minerals are…
Arranged in regular patterns and made
of crystals (crystal structure)
Some minerals are metals.
Aluminum
Gold
Some examples of minerals are
Minerals form from…
Dissolved in a liquid
Melted
Materials
Part Two
Text pgs. 121-126
How do we identify minerals?
Properties of Minerals
Each mineral has its own specific
properties that can be used to
identify it. You may need to
conduct some tests to identify the
mineral.
Scientists classify, or group and describe,
minerals in many ways. They classify
minerals by color, luster, texture, hardness,
and streak.
galena
vanadinite
malachite
sulfur
The color (physical property) of the mineral
depends on the chemicals in them.
Luster is the
amount of light
reflected from
the mineral’s
surface (how
shiny it is).
Quartz has a
glassy luster.
It looks like
glass.
Magnetite and Purpurite have a
metallic luster. They look like shiny
metal.
Peridot has a waxy luster. It
looks as if it is covered with wax.
Kaolinite has a dull luster. It
does not reflect much light, and is
not very shiny.
Copper - ???
Gold - ???
Peridot - ???
Calcite - ???
Texture describes how a mineral feels. Minerals may
be rough, smooth, bumpy, or soapy. Can you guess which
mineral has each texture?
Gold - BUMPY
Copper - SMOOTH
Peridot - SOAPY
Calcite - ROUGH
1. Talc
2. Gypsum
3. Calcite
4. Fluorite
5. Apatite
6. Orthoclase/ Feldspar
7. Quartz
8. Topaz
9. Corundum
10.Diamond
All minerals are hard,
but some are harder
than others. Scientists
test the hardness of a
mineral by trying to
scratch it. Scientists
use the Mohs Hardness
Scale to rate a
mineral’s hardness.
Minerals at the top of
the scale are soft and
easy to scratch. Those
at the bottom are hard
and difficult to scratch.
Diamond –
the hardest
mineral
talc – the
softest mineral
feldspar
apatite
Diamonds are the hardest minerals. It is almost
impossible to scratch a diamond. Talc is the softest
mineral. You can scratch it with your fingernail. Apatite
and feldspar have medium hardnesses.
Some minerals leave a trail, or streak, when
rubbed on a hard surface. Scientists
classify minerals by the color of their
powder. Hematite leaves a red-brown
streak.
image © Ra’ike, CC-SA license
Pyrite leaves a black streak.
Rhodochrosite leaves a white
streak.
Crystal Systems
The crystals of each mineral from atom by
atom to form the mineral’s crystal structure.
Geologists classify these structures into six
groups based on the number and angle
of the crystal faces.
Group - Example
Cubic - Magnetitie
Hexagonal - Quartz
Tetragonal – Rutile
Orthorhombic - Sulfur
Monoclinic - Azurite
Triclinic – Microcline Feldspar
Cleavage and Fracture
A mineral that splits
easily along flat
surfaces has the
property of cleavage.
Fracture
Fracture describes
how a mineral looks
when it breaks
apart in an
irregular way
image © Ra’ike, CC-SA license
Density is the mass in a given space divided
by its volume. No matter what the size of a
mineral sample, its density is always the
same.
Specific Gravity
a mineral’s density in water is known as its specific gravity at a certain
temperature
Examples
The specific gravity of gold is
19.3 g/cm3
Aluminum’s specific gravity
is 2.70 g/cm3
Special Properties
Fluorescence – reacts to
ultraviolet light
Magnetic attraction
Reacts to an acid
Radioactive, Conducts electricity,
etc.
Why is it important to learn about
minerals?

Minerals are made as part of the Earth’s
constructive process. We use these minerals in
many ways in our daily lives.
Are minerals a renewable resource?
Why or why not?
No, it can take many years to replace the minerals
as part of the Earth’s constructive process.
Part Three
How do minerals form?
 text pgs. 128-132

More about how minerals form
In general, minerals can form in two ways: through crystallization
of melted materials and through crystallization of materials
dissolved in a liquid. The process through which atoms are arranged
to from a material with a crystal structure is referred to as
crystallization.
Minerals from Magma
Minerals form as hot magma cools inside the Earth’s crust or
as lava hardens on the surface. When liquids cool to a solid
state, they form crystals. The size of the crystal depends on
several factors: the rate at which magma cools, the
amount of gas the magma contains, and the chemical
composition of the magma all affect crystal size.
When magma/lava cools slowly deep in the Earth’s surface,
large crystals form.
When magma/lava cools quickly, small crystals form.
Minerals from hot water solutions
time lapse of growing crystal
Sometimes minerals dissolve in solutions. A solution is
a mixture in which one substance dissolves in another.
When a hot water solution begins to cool, the elements
and compounds leave the solution and begin to
crystallize as minerals. Pure metals that crystallize
underground form veins. A vein is a narrow channel or
slab of a mineral that is different from the rock
surrounding it. Often these mineral form where tectonic
plates spread apart forming chimneys along the midocean ridge.
Other minerals can be seen when the solution
evaporates. One example of this is the mineral halite
(salt).
Part Four
How do we use minerals?
Mineral Resources
Text pgs. 134-139
Minerals are the sources of metals, gemstones, and other
materials used to make many products that we use today.
What is an ore?
A rock that contains a metal or
economically useful mineral is
called an ore. Most metals do
not occur in pure form. A metal
usually occurs as a mineral in a
combination of metal and other
elements. Much of the world’s
copper is found in an ore
containing the mineral
chalcopyrite. They must be
separated from their other
elements in the ore. Bauxite is
an ore for aluminum.
Smelting
Ores must be processed before the metals they
contain can be used. After miners remove ore from a
mine, smelting is necessary to remove the metal from
the ore. In the process of smelting, an ore is melted
to separate the useful metal from the other elements
the ore contains.
After smelting, additional
processing may be needed to
get rid of impurities. One
example is the creation of steel,
an alloy – a solid mixture of two
or more metals.
How steel is made
Get ready to Rock!