BIG IDEA:
Rocks and minerals have properties
that can be: observed, tested,
described, identified and recorded.
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What does the object look like?
Where have you seen it before?
What is it used for?
What do you think it is?
The geologist was very interested in your rock dissection reports
and was happy to see that you were able to identify the 3 mystery
minerals found in your rocks. He knows your principal really wants
to find out what the rocks in his collection are, so he has sent
some final information and materials to help us complete our rock
identification. The geologist wanted me to tell you that rocks can
sometimes be very difficult to identify because they are
composed of a mixture of minerals and other materials. In order
to identify the rocks in our principal’s collection we will need to
look very closely at the rocks properties and use all of the
information we have in our scientist notebook concerning minerals
and the rock cycle. Because rocks can be very difficult to
identify, the geologist believes we should start by sorting the
rocks into categories by which they were formed and describe the
properties we observe.
What does the geologist want us to do?
What did the geologist give us to help?
What is the problem we need to solve?
How can we…
I think that we can…because…
In many of our lessons we have talked about the way
rocks are formed. The geologist said that this is a big
clue in helping us identify rocks. If a geologist is able to
know the geography, or area the rock was found, it can
be very helpful for identification.
 What are the three main earth processes in which
rocks are formed?
igneous, metamorphic, and sedimentary
Igneous rock is formed by the cooling of melted rock.
This melted rock is referred to as magma or lava
depending on where it is found.
Lava
Magma
Molten rock below the
earth’s surface.
Molten rock that has spewed
above the earth’s surface.
 If igneous rock is formed when lava or magma is cooled,
what do you think this rock may look like?
 glassy, bubbled and porous texture, pattern of crystals
 Where do you think you are most likely to find igneous
rocks?
 Areas with volcanic activity
Sedimentary rocks form in a much different way than
igneous rocks. They are formed from layers of sediment
that accumulate like the layers of sediment you found in
your vials during the rock dissection. Sediment can be
mud, sand, small pebbles and the remains of living
organisms. The sediment is mostly rock materials that
have been broken down from weathering or erosion.
 What do you think sedimentary rock might look like?
 layered appearance, sandy, fine grained texture
 Where do you think you are most likely to find
sedimentary rocks?
 Locations that were once under water
Metamorphic rocks require great deals of heat and pressure
to form. A clue to helping you remember this type of rock is
to think about just part of the word…
morphic.
A caterpillar goes through a state of metamorphosis when it
changes into a butterfly. Metamorphic rocks are existing
rocks that change because of intense pressure and heat.
 What do you think metamorphic rocks look like?
 Compact, sparkling, texture
 Where do you think you are most likely to find
metamorphic rocks?
 Mountainous regions because of the intense pressure
required from the earths plates colliding when they form
mountains.
Who can tell us what a fossil is?
A rock that contains remains of a plant or animal.
Which kinds of rock would you find fossils?
Sedimentary and Metamorphic
Igneous Rock
How they are formed:
 Molten rock that cools
Properties/Characteristics:
 Glassy
 Bubbled or porous
 Pattern of crystals
 Light weight
Location Found:
 Near volcanic activity
Sedimentary Rock
How they are formed:
 Layers of sediment that
have been deposited
 Contain rocks that have
been eroded or
weathered (mud, sand,
pebbles, gravel…)
Properties/Characteristics:
 Layered
 Sandy fine texture
 Soft
 Dull
Location Found:
 Areas once covered by
water
Metamorphic Rock
How they are formed:
 Intense heat and
pressure
 Rocks that have been
changed
Properties/Characteristics:
 Compact
 Sparkling
 Coarse Texture
Location Found:
 Mountainous areas
How can a geologist predict the properties a rock may
have based on how it was formed?
Using the information you have for the forms of rocks in
your science notebook, and resources from our object wall,
I want you to do your best to sort the rocks in to 4 groups:
Igneous, Sedimentary, Metamorphic, and Fossils.
The geologist said this can be a difficult task! Make sure
you record your information in your scientist notebook and
describe the properties that helped make your decision.
Rock #
Igneous
Sedimentary
Metamorphic
Fossils
Properties
Our geologist recommended that we start identifying our rocks
based on how they were formed. This has allowed us to group our
rocks by similar properties and narrows the possibilities for
properly identifying each rock in our principal’s collection.
The geologist has sent an additional rock guide that should help us
identify and name each of our rocks.
Using the new Rock Data Sheet, try to correctly identify each of
your rocks. You will want to use all of the data you have collected
in your scientist notebook. You may even need to complete some
additional mineral tests and collect more data.
Remember that since these are rocks that are made of different
minerals and materials, the mineral tests will not always work.
The minerals may be too small or buried in the rock.
You are not allowed to dissect the rock
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How do geologists identify rocks?
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How can a geologist predict the properties a rock may
have based on how it was formed?
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How they are formed
Properties and Characteristics
Location found
Igneous, Sedimentary, and Metamorphic rocks have unique
properties and characteristics.
What can the properties of a rock tell us about the
rocks origin?
Igneous rocks would come from areas of previous volcanic
activity.
 Sedimentary rocks would come from areas that were once
covered in water.
 Metamorphic rocks would come from mountainous areas where
the earths plates are colliding.
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Based on what you have learned from your investigation
of rocks, you need to record at least 3 claims and
evidence statements in your science notebook.
I claim that…
I know this because…
Possible Examples:
I claim that geologists can identify rocks based on
their origin and properties. I know this because…
I claim that igneous rocks can be glassy and may
contain bubbles. I know this because…
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What did you learn…?
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What really surprised you…?
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What new questions do you have…?
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What would you like to know more about…?