1. Rocks & Minerals

2. Minerals

3. What is a Mineral? Naturally Occurring Inorganic Solid
Definite Chemical Formula
Definite Crystal Structure

4. Naturally Occurring Formed by natural processes not in the laboratory
- Is an Ice Cube a mineral?
- Is the ice on the windshield of a car a
mineral?

5. Inorganic Formed by inorganic processes; not living
Does not contain chains of carbon atoms

6. Solid Not gas or liquid -H2O as ice in a glacier is a mineral, but
water is not

7. Definite Crystal Structure
Highly ordered atomic arrangement of atoms in regular geometric patterns
Apatite
Feldspar
Diamond
Quartz 8

8. Definite Chemical Formula
Minerals are expressed by a specific chemical formula
-Gold (Au)
-Calcite (CaCO3)
-Quartz (SiO2)
-Pyrite (FeS2)

9. Composition of the Earth’s Crust
Eight Elements that make up over 98% of Earth’s Crust
-Oxygen (O)
-Silicon (SI)
-Aluminum (Al)
-Iron (Fe)
-Calcium (Ca)
-Sodium (Na)
-Potassium (K)
-Magnesium (Mg)

10. Where Do Minerals Come From?
Magma
Evaporation

11. How Are Minerals Identified?
Color
Luster
Hardness
Streak
Density
Crystal Shape
Cleavage and Fracture
Special Properties

12. Color Usually the first and most easily observed
-Some minerals are always the same color
-Some minerals can have many colors
ROSE QUARTZ
QUARTZ
SMOKY QUARTZ

13. Luster General appearance of a mineral surface in reflected light
Glassy-Obsidian

14. Hardness Resistance to scratching by different items; “scratchability”
Mohs Hardness Scale
>2 fingernail
3 penny
~5 Steel of a pocket knife
5.5 Window Glass
6.6 Steel of a file
7 quartz crystal

15. Mohs Mineral Hardness Scale
1) Talc
2) Gypsum
3) Calcite
4) Flourite
5) Apatite
6) Feldspar
7) Quartz
8) Topaz
9) Corundum
10) Diamond
Softest 1 9 5 2 6 10 3 7
Hardest 4 8

16. Streak The color of a finely powdered mineral
Determined by rubbing the mineral on a piece of unglazed porcelain (streak plate)

17. Density
The amount of matter in a given space (Mass/Volume)

18. Crystal Shape
Minerals have a characteristic crystal shape resulting from the atomic packing of the atoms when the mineral is forming

19. Cleavage and Fracture
Cleavage is the tendency of a mineral to split or crack along parallel or flat planes
Fracture occurs when a mineral breaks at random lines instead of at consistent cleavage planes.
BIOTITE
QUARTZ
Obsidian
1 Direction of Cleavage
No Cleavage
Conchoidal Fracture

20. Special Properties Magnetism (Magnetite)
Glowing under ultraviolet light (Fluorite)
Salty taste (Halite)
Smell (Sulfur)
Reaction to HCl (Calcite)
Magnetite

21. Economic Importance of Minerals
Minerals are in many things we see and use everyday such as; bricks, glass, cement, plaster, iron, gold

22. Every American Requires 40,000 Pounds of New Minerals per Year
at this level of consumption the average newborn infant will need a lifetime supply of:
-795 lbs of lead (car batteries, electric components)
-757 lbs of zinc (to make brass, rubber, paints)
-1500lbs of copper (electrical motors, wirings
-3593 lbs aluminum (soda cans, aircraft)
-32,700 lbs of iron (kitchen utensils, automobiles, buildings)
-28,213 lbs of salt (cooking, detergents)
-1,238,101 lbs of stone, sand, gravel, cement (roads, homes, etc.)

23. Rocks

24. Rocks Made of two or more different minerals that have been:
cemented together
squeezed and heated together
melted and cooled together.

25. Types of Rocks
Igneous
Sedimentary
Metamorphic

26. Igneous Rocks
Most igneous rocks are produced deep underground by the cooling and hardening of magma

27. Sedimentary Rocks
Formed from the breaking apart of other rocks (igneous, metamorphic, or sedimentary rocks) and the cementation, compaction and recrystallization of these broken pieces of rock

28. Fact about the Mississippi River
Did You Know?
The Mississippi River carries an average of 436,000 tons of sediment each day
It moves an average of 159,000,000 tons of sediment a year

29. Metamorphic Rocks
Formed from heat and pressure changing the original or parent rock into a completely new rock. The parent rock can be either sedimentary, igneous, or even another metamorphic rock.

30. The Rock Cycle
The diagram of the rock cycle shows how the earth's rocks are changed again and again

31. Classification of Igneous Rocks
Composition-refers to the minerals that make up the rock
Texture-shape, size, arrangement and distribution of minerals that make up the rock

32. Composition Extrusive- Formed from lava; volcanic
Intrusive- Formed deep within the earth
Obsidian
Pumice
Granite

33. Textures Coarse-grained Glassy Porphyritic Fine-grained Obsidian
Granite
Basalt
Granite

34. Classification of Sedimentary Rocks
Clastic Rocks- Made of the fragments of previously existing rocks
Organic Rocks- Come from organisms
Chemical Rocks- Formed by inorganic processes such as evaporation

35. Clastics Rocks
Conglomerate
Sandstone
Mudstone

36. Fossiliferous Limestone
Organic Rocks
Limestone
Coquina
Fossiliferous Limestone

37. Chemical Rocks
Limestone

38. Metamorphic Rocks
Foliated- Parallel alignment of flattened mineral grains and pebbles
Unfoliated-Rocks that are not banded and do not break into layers

39. Foliated
Gneisse

40. Unfoliated
Marble

41. Distribution of Rocks in the U.S.