2. sulfur
gold
Minerals
malachite
rhodochrosite

3. 2.2 Minerals Definition of a Mineral 1. Naturally occurring
2. Solid substance
3. Orderly crystalline structure
4. Definite chemical composition
5. Generally considered inorganic

4. 2.2 Minerals How Minerals Form 1. Crystallization from magma
2. Precipitation
3. Pressure and temperature
4. Hydrothermal solutions

5. 2.2 Minerals Mineral Groups
 Can be classified based on their composition
1. Silicates
Silicon and oxygen combine to form a structure called the silicon-oxygen tetrahedron. This provides the framework of every silicate mineral.
Ex. Quartz, Feldspar, Olivine, Mica

6. The Silicon-Oxygen Tetrahedron

7. 2.2 Minerals Mineral Groups 2. Carbonates 3. Oxides
Contain the elements carbon, oxygen, and one or more other metallic elements
EX. Calcite, Dolomite
3. Oxides
Contain oxygen and one or more other elements, which are usually metals
Ex. Corundum, Hematite

8. 2.2 Minerals 4. Sulfates and Sulfides 5. Halides 6. Native elements
Contain the element sulfur
Sulfates also contain Oxygen
Ex. Galena, Pyrite, Sphalerite
5. Halides
Contain a halogen ion plus one or more other elements
Ex. Fluorite, Halite
6. Native elements
Exist in relatively pure form
Ex. Gold, Diamond, Lead, Silver

9. 2.3 Properties of Minerals
Color
2.3 Properties of Minerals
Small amounts of different elements can give the same mineral different colors.
Streak
Streak is the color of a mineral
in its powdered form.

10. 2.3 Properties of Minerals
Luster
2.3 Properties of Minerals
 Luster is used to describe how light is reflected from the surface of a mineral.
Think “shiny” and “dull”
 Pyrite (Fool’s Gold)

11. 2.3 Properties of Minerals
Crystal Form
2.3 Properties of Minerals
 Crystal form is the visible expression of a mineral’s internal arrangement of atoms.

12. 2.3 Properties of Minerals
Hardness
2.3 Properties of Minerals
 Hardness is a measure of the resistance of a mineral to being scratched.
 Mohs scale consists of 10 minerals arranged from 10 (hardest) to 1 (softest).

13. 2.3 Properties of Minerals
Cleavage
2.3 Properties of Minerals
 Cleavage is the tendency of a mineral to cleave, or break, along flat, even surfaces.

14. 2.3 Properties of Minerals
Fracture
2.3 Properties of Minerals
 Fracture—the uneven breakage of a mineral

15. 2.3 Properties of Minerals
Density
2.3 Properties of Minerals
 Density = Mass / Volume
Distinctive Properties of Minerals
fluorescence, optical properties, radioactivity, magnetism, taste, and reactions to chemicals.

16. Just Read !
MINERALS
To be classified as a mineral a substance must meet all of the following characteristics:
Inorganic (not formed by life processes)
Formed in nature (synthetic substances are not considered minerals)
Solid
Atoms have the same crystalline pattern (crystal shape is visible, but few are perfect).
Identifiable chemical composition (has the same kinds of atoms arranged throughout in the same way and in the same proportions).
In summary, a mineral is a naturally occurring, inorganic solid that has a definite chemical composition and crystal structure.

17. How common are minerals?
Just Read
There are about 3500 known minerals
The 20 most common minerals make up 95% of the Earth’s crust
ALL rocks are composed of minerals
Aquamarine 

18. Common Uses of Minerals
Just Read
Common Uses of Minerals
MINERAL
USE
copper
electrical wiring, coins
gold
computer circuitry , UV protection for astronauts
magnetite
natural magnet
halite
table salt
fluorite
toothpaste
galena
car batteries, iron extraction
molybdenite
steel and soil additive
sulfur
matches
zeolite
water softener
diamond
drills

19. marble (metamorphic limestone) ...more metamorphic rocks
igneous rocks R O C K S
conglomerate rocks
sandstone
marble (metamorphic limestone)
...more metamorphic rocks

20. 3.1 The Rock Cycle Rocks  Rocks are any solid mass of mineral
 3 Types of Rocks
1. Igneous rock - formed by the crystallization of molten magma.

21. 3.1 The Rock Cycle Rocks  Types of Rocks
2. Sedimentary rock - formed from the weathered products of preexisting rocks that have been compacted, and cemented.
3. Metamorphic rock - formed by the alteration of pre-existing rock deep within Earth by heat and pressure

22. Energy That Drives the Rock Cycle
Rock Cycle shows the interrelationships among the three rock types
Energy That Drives the Rock Cycle
Heat from the Earth’s interior
Energy from the sun
- powers weathering processes

24. 3.2 Igneous Rocks Formation of Igneous Rocks
Intrusive igneous rocks are formed when magma hardens beneath Earth’s surface. Cools very slowly!
Ex. Granite *larger crystals
2. Extrusive igneous rocks are formed when lava hardens. Cools quickly!
Ex. Obsidian *smaller crystals

25. 3.2 Igneous Rocks Classification of Igneous Rocks
 Classified based on composition & texture.
1. Texture
• Coarse-grained texture is caused by slow cooling resulting in larger crystals.-intrusive
• Fine-grained texture is caused by rapid cooling resulting in smaller, interconnected mineral grains.- extrusive

26. Classification of Igneous Rocks

27. 3.3 Sedimentary Rocks Formation of Sedimentary Rocks
• Erosion involves the weathering and the removal of rock.
• Deposition occurs when an agent of erosion—water, wind, ice, or gravity—loses energy and drops sediments.

28. 3.3 Sedimentary Rocks Formation of Sedimentary Rocks
• Compaction is a process that squeezes, or compacts, sediments.
• Cementation takes place when dissolved minerals are deposited in the tiny spaces among the sediments.
(holds the material together like glue)

29. 3.3 Sedimentary Rocks Classification of Sedimentary Rocks
1. Clastic sedimentary rocks are composed of weathered bits of rocks and minerals.
• Classified by particle size
• Common rocks include
- Shale, Sandstone, Conglomerate

30. 3.3 Sedimentary Rocks Classification of Sedimentary Rocks
2. Chemical sedimentary rocks form when dissolved substances precipitate, or separate, from water.
Common rocks include
Limestone, Coal

31. 3.3 Sedimentary Rocks
 Features of sedimentary rocks are clues to how and where the rocks are formed

32. 3.4 Metamorphic Rocks Formation of Metamorphic Rocks
 Metamorphism means “to change form.”
 Most metamorphic changes occur at elevated temperatures and pressures.
Conditions for formation are found a few kilometers below the Earth’s surface and extend into the upper mantle.

33. 3.4 Metamorphic Rocks Formation of Metamorphic Rocks
 Contact metamorphism occurs when magma moves into rock.
Regional metamorphism results in large-scale deformation and
high-grade metamorphism.

34. 3.4 Metamorphic Rocks Agents of Metamorphism  Heat  Pressure
Provides the energy needed to drive chemical reactions
 Pressure
Causes a more compact rock
with greater density

35. 3.4 Metamorphic Rocks Classification of Metamorphic Rocks
 Two main categories
1. Foliated Metamorphic Rock
Has a banded or layered appearance
Ex. Gneiss
2. Nonfoliated Metamorphic Rock
Does not have a banded texture
Ex. Marble

36. Classification of Metamorphic Rocks

37. This process can take billions of years!