Unit C
Chapter 2
ROCKS AND MINERALS
WHAT ARE MINERALS?
Mineral
Sample
Color of
Mineral Sample
1
3
5
7
8
10
Color of
Mineral Streak
Things that Scratch
The Mineral
MINERALS



Mineral – is always a
solid material with
particles arranged in a
repeating patters.
The pattern is called a
crystal.
Minerals form in
different ways, some
form in Earth’s mantle,
others form on the
surface of the Earth.

Minerals can look very
different depending on
how and where they were
formed.
PROPERTIES OF MINERALS


Streak – is the color of
the powder left behind
when you rub a mineral
against a white tile.
Luster – describes the
way the surface of the
mineral reflects light


Ex. Aluminum foil has a
metallic luster.
Hardness – is a mineral’s
ability to resist being
scratched.
USE OF MINERALS

Minerals can be used in
a variety of ways.





Jewelry
Musical Instruments
Electric wiring
Pencils
Table Salt
IDENTIFYING ROCKS
Rock
Sample
1
2
3
4
5
Color
Texture
Picture
Bubbles
When
Vinegar
Added
TYPES OF ROCKS



Rock – is a material
made up of one or more
minerals.
There are many
different kinds of rocks,
and they form in
different layers of the
Earth.
There are three main
categories rocks can be
classified in.

Main Types of Rocks
1.
2.
3.
Igneous
Sedimentary
Metamorphic
IGNEOUS ROCKS



Igneous rocks form
when melted rock
hardens.
Fine-grained – rocks
that form from magma
that cools quickly.
These rocks have small
mineral pieces.
Coarse- grained – rocks
that form from lava that
cools slowly.

Fine-grained

Coarse-grained
SEDIMENTARY ROCKS



Sedimentary rocks form
over a long period of time
as they are squeezed and
stuck together.
The rocks are made of
eroded material that is
deposited at the bottom
of streams, rivers and
lakes.
The largest pieces are
dropped first.

Conglomerate – is a type of
sedimentary rock that can
for from large pieces


Some can pieces can be as
large as boulders.
Limestone – is a fine
grained sedimentary rock
that form in oceans,
sometimes even including
seashells.
METAMORPHIC ROCKS


Metamorphic rocks form
under high heat and
great pressure that can
change a rock.
Metamorphic rocks can
form from any kind of
rock – sedimentary,
igneous, or even other
metamorphic rocks.


Metamorphic rocks c an
form as mountains are
built up. They also form
as other rocks are
squeeze and heated.
Types:
1.
2.
3.
Gneiss
Marble
Quartzite
ADDITIONAL QUESTIONS
1.
Which would be a better model of how an igneous rock
changes into a sedimentary rock- an eraser rubbed on
paper, or crushed graham crackers that are mixed with
melted butter and pressed into a pie pan to make
crust? EXPLAIN your answer.
2.
Which could be a better model of how metamorphic
rocks form- chocolate chip cookie dough that is
flattened and than baked into cookies, or chocolate
chips mixed with butter and melted together in a pan
and then cooled to make fudge? EXPLAIN your answer.
ROCK CYCLE



A rock can begin as one
type and be changed
many times.
Change takes many
thousands of years.
This never ending rock
change is called the
rock cycle.