1. Rocks, Minerals and Soil
Third Grade
Earth Science

2. Rocks

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

4. 3 Types of rocks
Sedimentary
Igneous
Metamorphic

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

6. Metamorphic Rocks

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

8. 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.

9. 4 ways to identify rocks
Texture
Color
Size
Hardness

10. 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.

11. 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

12. 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.

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

14. Minerals

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

16. 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.

17. 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

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

19. Fossils

20. What are fossils?
A fossil is a mark or the remains of something that was once living.

21. 4 Types of Fossils
Mold
Cast
Trace
True-form

22. Mold Fossil
A mold fossil is a impression made in a substance. It is not the actual living organism but a impression.
The picture is a mold fossil of a leaf.

23. Trace Fossil
Trace fossils are impressions like mold fossils but are not the actual living organism- just evidence of them.
Examples: nests, burrows, and footprints.

24. True-Form Fossils
True form fossils are the actual once living animal or organism.
Example: Animal bones

25. Cast Fossil
A cast fossil is formed when a mold fossil is filled in. The fossil can be of anything that once lived (plants, animals, insects).

26. Soil

27. Types of Soil
Clay
Sandy soil
Potting soil
Loam

28. 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.

29. Sandy Soil
When you rub sand, it feels rough. This is because it has sharp edges. Sand doesn't hold many nutrients.

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

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