Rocks minerals and soil

Rocks, Minerals and
Soil
Third Grade
Earth Science



What are rocks?
• Rocks are solid
materials that
are made of one
or more
minerals.


3 Types of rocks
1. Sedimentary
2. Igneous
3. Metamorphic


Metamorphic Rock
• Metamorphic
rock is rocks
that have been
changed by heat
and pressure.


Metamorphic Rocks

Sedimentary Rock
• Sedimentary rocks form when
materials settle into layers and
harden.
• Any rock can become
sedimentary if at the surface.


Igneous Rock
• Igneous rock is a rock
that was once melted
but has cooled and
hardened.
• Hot lava comes out
from within the earth
and is an igneous rock
once cooled.


4 ways to identify rocks
1.
2.
3.
4.

Texture
Color
Size
Hardness

EXPERIMENT TIME!!!
• You are all now junior
geologist. A geologist is
someone who studies
the Earth. We will test
the hardness of rocks
using Moh’s scale.


Moh’s Hardness Scale
• With your group, test the
hardness of rocks and give it a
score of 1 to 10.
• Soft: scratches with fingernail
1 or 2
• Medium/Soft: scratches with a
penny 3 or 4
• Medium/Hard: scratches with
a nail 5 or 6
• Hard: will not scratch 7 or 8


Moh’s Scale
• Working as a group, make a bar
graph with your group rating your
rocks from softest to hardest. Be
sure your graph is labeled and
colorful.

Classify rocks
•
1.
2.
3.
4.

As a group, discuss classifications of your rocks. Remember the 4
ways to classify rocks.
Color
Size
Texture
Hardness



What are minerals?
• Minerals are
solid natural
made objects
that have never
been alive.
Minerals can be
rock-like or
metals.


How are rocks and minerals different?

• Rocks are made up of
minerals. Minerals are
within all rocks. The
minerals in rocks are
what makes rocks look
different from other
rocks.


Rocks and Mineral
Minerals

Rocks

Usually very pretty

Not pretty

Has a shape

No shape

May contain crystals

No crystals

Will not contain fossils

May contain fossils

Color is mostly the same May have many colors


Identify the Minerals
Time to Play a Game…. How many minerals can you find in the
kitchen? (click on refrigerator)



Types of Soil
1. Clay
2. Sandy soil
3. Potting soil
4. Loam


Clay
• Clay is smooth when dry
and sticky when wet.
Soils high in clay
content are called heavy
soils. Clay also can hold
a lot of nutrients, but
doesn't let air and water
through it well.


Sandy Soil
• When you rub
sand, it feels

rough. This is
because it has
sharp edges. Sand
doesn't hold many
nutrients.


Loam
• Loam is a mixture of
different types of
soils. Loam soils feel
smooth and spongy
when rolled into a
ball.


Potting Soil
• Potting soil is soil
mixture made for
use in gardens and
potted plants.
Potting soil should
be loose and light.