1. Earth Materials

2. Minerals Mineral – an inorganic solid material found in nature
More than 4000 known!
Each mineral has specific properties
Inorganic – something not made by plants or animals

3. Minerals Minerals must always have the same chemical make-up
The atoms that make up calcite are always the same

4. Some Minerals Garnet – sand paper, electronic components, glass
Granite – sculptures, countertops, blocks for foundations
Graphite – pencils, making steel, dry lubricant
Halite – SALT!
Pyrite – fools gold
Quartz – melted to make glass

5. Rocks!
Rock – combination of two or more minerals

6. How do Minerals Form
Minerals form in different ways and you can tell by how they look
Form from melted rock called magma
When the magma cools similar atoms form together
When solutions evaporate
As water leaves a solution the minerals are left behind
From settling out as a solid material

7. How do Minerals Form From magma From solution
The grains of the mineral fit together like a puzzle
Glassy shiny appearance
From solution
Usually form crystals or layers

8. Properties of Minerals
Most properties of minerals are easy to identify
Crystals – solid materials arranges with atoms in a repeating patter; smooth surfaces, sharp edges, and points

9. Properties of Minerals
Minerals can also be identified by how they break!
Cleavage – when minerals break into pieces with smooth, regular edges
Fracture – when minerals break into random jagged pieces

10. Mineral Cleavage

11. Streak and Luster
Color is a useful tool to determine what mineral you have but color can fool you!
Pyrite (fool’s gold) is shiny and gold in color…but it isn’t real gold!
How can we tell?!

12. Streak and Luster
Streak test – scratch a mineral across the surface of a white tile; leaves behind a streak of color

13. Streak and Luster Shiny? Dull? Pearly?
Luster – how light reflects off the surface of a mineral
Metallic mineral– shines like a metal
Nonmetallic mineral – dull, earthy luster

14. Mineral Hardness Some minerals are harder than others
Talc is very soft and can be scratched with a finger nail
Diamond is incredibly hard and can cut almost any other material on Earth!

15. Diamonds
If diamond is one of the hardest materials we have here on Earth, how do we go from this…
To this!

16. Mohs Scale of Hardness
Friedrich Mohs was an Austrian geologist who developed a way to classify minerals by their hardness
Mohs Scale – scale from 1 (softest) to 10 (hardest) classifying the hardness of minerals

18. Identifying Minerals
We can identify minerals based on their hardness with a homemade identification kit!
Penny
Nail
Glass plate

19. Other Mineral Properties
There are a few other unusual properties we can use to identify minerals
Some minerals are magnetic!
Magnetite
Some minerals fizz when they come in contact with a mild acid
Calcite
Halite even tastes salty!
(but don’t lick it…that’s just gross)

20. Gems Would you rather have a diamond ring or a quartz ring?
Probably diamond because it is rare so it is worth a LOT more money!
Gem – rare minerals that can be cut and polished giving them a beautiful appearance

22. Ores We can get many useful materials from minerals
Ore – a mineral containing something useful and sold for a profit
Many metals we use come from ores
Iron from hematite
Lead from galena
Magnesium from dolomite

23. 5 things…
Can you name five things in the room that were made from minerals?
What mineral was used to make each?

24. Rocks Rock! It seems like rocks have been around on Earth forever!
Rocks have been around but things are constantly changing
Changes produce 3 main types of rock
Igneous
Metamorphic
Sedimentary

25. Igneous Rock
Igneous Rock – formed when melted rock, magma, from inside the earth cools
Extrusive
Intrusive

26. Igneous Rock
Extrusive Igneous Rock – when magma cools on the Earth’s surface
Lava - magma that has reached the Earth’s surface
Cool quickly
No time for crystals to form
Smooth or glassy look
Basalt
Rhyolite

27. Igneous Rock
Intrusive Igneous Rock – when magma cools below the Earth’s surface
Cools slowly
Time for large visible crystals to form
Granite
Diorite

28. Sedimentary Rock
Sedimentary Rock – made of pieces of other rocks, plant and animal matter, or dissolved minerals collect and form rock layers
Sediments – pieces of rock and other materials

29. Sedimentary Rock
Sediments can be carried by rivers, oceans, waves, mudslides, glaciers, and the wind!
Sediments settle in layers when they are deposited
Most sedimentary rock forms over thousands of years
Sandstone
Shale

30. Sedimentary Rock
Most sedimentary rocks are named for the size particle they are made of
Largest – Conglomerate
Sand grains – Sandstone
Silt sized grains (smaller than sand) – Siltstone
Smallest grains (clay) - Shale

31. Sedimentary Rock
Conglomerate
Siltstone
Shale
Sandstone

32. Chemical Rocks
Chemical sedimentary rocks are formed when mineral rich water evaporates
From seawater
Geysers or springs
Layers of minerals are left behind
Limestone
Dolomite

33. Biochemical Rocks Biochemical rocks form over millions of years
Living matter dies and piles up
Coal is formed from layers pf plants piled on top of each other
The White Cliffs of Dover in England are made of chalk
Millions of tiny sea creatures (shells, algae) died and fossilized

34. Sedimentary Rock
Sedimentary rock is the ONLY TYPE of rock we can find fossils in!
Fossil – preserved remains or impression of a prehistoric organism

35. Metamorphic Rock The Earth’s surface is constantly changing
Earthquakes shake and move land
Volcanos bring melted rock to the surface and bury other layers of the Earth beneath them

36. Metamorphic Rock
As the land is constantly changing igneous and sedimentary rocks are burying and heated and squeezed under ground
Metamorphic rock – rocks formed when older rocks are heated and squeezed
Metamorphic means “to change form”
Schist
Gneiss

37. Metamorphic Rock

38. Metamorphic Rock Two types of metamorphic rock
Foliated – rocks have bands, or layers
Non-foliated – no distinct bands or layers
Soapstone
Non-foliated
Slate
Foliated

39. The Rock Cycle
Rock Cycle – shows how rocks can be changed from one type to another