1. Minerals and Rocks

2. How are minerals related to rocks?
All rocks are made of minerals.
Those rocks made of one mineral are called monominerallic rock. Mono means one!
Those made of 2 or more minerals are polyminerallic rocks. Poly means more than one!

3. What are Minerals?
They are: “Naturally occurring, inorganic, solid, with a definite chemical composition, and a definite crystal structure.”

4. How do minerals get their chemical and physical properties?
Properties result from the specific internal arrangement of atoms within the mineral itself
For example, how hard a mineral is, what crystal shape the mineral has etc. are all caused by the arrangement of it’s atoms/molecules.

5. Silicon-Oxygen Tetrahedron
The most common arrangement is the silicon-oxygen tetrahedron of the silicate minerals which are in great concentration in the crust
Looks Like:
Note the pyramidal shape!
Examples:
Feldspars: most abundant minerals
Quartz: second most abundant

6. Carbonate Minerals
Have CO3 (carbonate group) as their constituent units
Calcite: CaCO3

7. Silicates
Quartz: Chemical Formula: SiO2

8. Oxides
Hematite: Chemical Formula: Fe2O3

9. Physical Properties of Minerals; used for identification
Mineral ID is accomplished through the use of a combination of tests:
Color
Luster
Streak
Hardness
Cleavage and Fracture
Density and Specific Gravity
Special Properties (if they exist)

10. Color Most often used, but least reliable!
Many different minerals can have the same color
Olivine
Green Quartz

11. Luster The way a mineral reflects light Nonmetallic Luster:

12. Streak Color of a mineral when powdered
Done by scraping a mineral across an unglazed porcelain tile
Hematite has a reddish brown streak

13. Hardness The resistance of a mineral to being scratched
Compared to the 10 minerals of Moh’s Hardness Scale; Talc (1) to Diamond (10)

14. Cleavage and Fracture
Cleavage: when a mineral splits along flat planes
Fracture: when a mineral breaks irregularly
Muscovite: perfect cleavage

15. Density and Specific Gravity
Density of a mineral is a very specific characteristic
Specific Gravity: the ratio of the weight of a substance to the weight of an equal volume of water at 4ºC
Both properties are distinctive of particular minerals

16. Special Properties
Some minerals possess properties that are all their own:
Magnetite: Has enough iron in it to be attracted to magnets.
Iceland Spar Calcite: double refraction
Calcite: fizzes in the presence of HCl
Etc.
Ex. Iceland Spar:

17. Special Properties Continued
Pitchblende: Radioactivity: gives off invisible radiation
Fluorite: Fluorescence: some minerals glow in ultraviolet light

18. Using Common Properties of Minerals Homework
Complete the packet using the chart on the last page of your reference table.
Do your best!!!!

19. Classifying Minerals Lab
You will be identifying 8 unknown mineral samples on the basis of their physical and chemical properties
Work carefully.
Make sure to always wear your safety glasses.

20. Introduction to Rocks
Rocks: solid substances which are made of 1 or more minerals

21. Igneous Rocks Form from hot liquid rock. Two types:
1)Intrusive Igneous Rocks: form from hot liquid magma inside the earth. Cools SLOW!!! (underground)
BIG Crystals!

22. Igneous rocks continued:
2) Extrusive Igneous Rocks: Cool QUICKLY on the Earth’s surface from lava.
Have small crystals or none at all!
Lava is the same as magma. It’s name tells you it’s location.

23. Igneous Rocks: Composition
Classified by composition and texture
Composition:
Felsic (high aluminum content)
Lower density; lighter color
Mafic (high iron & magnesium)
Higher density; darker color

24. Igneous Rocks: Texture
Texture: gives clues about the environment the rock formed in
SLOWER COOLING produces:
Coarse Grained Texture:
Large crystals (1-10mm) means slow cooling deep underground
FAST COOLING produces:
A) Fine Grained Texture:
Small crystals (<1.0 mm) means fast cooling on the surface
B Glassy Texture:
NO CRYSTALS-nearly instantaneous cooling

25. Igneous Rock Key Words Molten: means liquid
Solidification: means freezing
Crystallization: means freezing
Vesicular: means has gas pockets (bubbles)
“IT IS AN IGNEOUS ROCK BECAUSE IT HAS INTERGROWN CRYSTALS!!”

26. Igneous Rock Classification Chart

27. Igneous Rock Chart Practice
Page 6 ref. tables
1. If an igneous rock has a lot of gas pockets, will it be called vesicular or non-vesicular?
2. What is the name of the igneous rock that has a low density, has a coarse texture and is intrusive?
3. Along the line that separates granite and diorite,,,,what is the percentage of plagioclase feldspar? (Measure and line up from zero.)
4. Name a mafic rock that is fine grained and vesicular.
5. A coarse grained rock is made up of 60% plagioclase feldspar, 18% biotite, and 22% amphibole. Name the rock……

28. Igneous Rock Exercise Homework
Answer the questions using page 6 of your reference tables.

29. Sedimentary Rocks 2 Main Groups:
1) Inorganic Land Derived Sedimentary Rocks
Rocks formed from sediments that are compacted and cemented
2) Chemically and/or Organically Formed Sedimentary Rocks

30. Inorganic Land Derived Sed. Rocks
Generally result from river, lake, or deep ocean deposits
Classification is based on SIZE of the sediment particles
Process of Formation:
Sediment is deposited
Sediment is compacted-pressed down
Sediment is cemented- “glued together”
Ex. Sandstone, conglomerate, siltstone, shale

31. Chemically and/or Organically derived Sed. Rocks
Chemical formation:
Evaporation of solutions
Precipitation of particles from solution
Ex: rock salt, rock gypsum, dolostone, chemical limestone
Organically formed:
Animals (shells): limestone
Plants : coal

32. Sedimentary Basin Diagram

33. Sedimentary Rock Classification Chart

34. Sedimentary Rock Key Words
Lithification: changing sediments to rock
Compaction: pressing sediments
Precipitation: crystallize out of solution
Stratification: layering
Fossils: only found in sed. rocks
Cementation: “gluing” sediments together
Clastic: pieces of other rocks
“It is a sedimentary rock because it has sediments cemented together!!”

35. Sedimentary Rock Exercise Homework
Answer each of the questions using page 7 of your reference tables

36. Metamorphic Rocks Metamorphic means “changed”
These rocks were once sedimentary, igneous or even metamorphic!
“Heated and squeezed” WITHOUT re-melting.
Commonly found along crustal plate boundaries where pressures are great.

37. Contact Metamorphism
A process where an igneous intrusion (a channel of hot magma moving up through the crust) comes into contact with neighboring rocks
This causes the parent rock (rock around it) to metamorphose

38. Metamorphic Rock ID Chart

39. Metamorphic key words
Foliated: Minerals have rearranged in to layers. Called banding when they can be easily seen. Ex. Gneiss
Non-foliated: Minerals may have grown but are not rearranged.
Distorted Structure: Fossils in once sedimentary rocks are stretched and out of shape due to extreme heat or once parallel layers are now wavy gravy!

40. Metamorphic Rocks Exercise Homework
Answer each of the questions using page 7 of your reference tables.

41. Rock Cycle
The continuous, dynamic set of processes by which rocks are changed into other types of rocks.
p. 6 Ref Tables:

42. “Rock ID Laboratory”
Move around the room and ID each of the numbered samples.
You can start anywhere, but you must attempt to ID each of the samples.

43. Climate, Rock, and Mineral Test
Prepare for the “rockiest” test you have ever taken!!!
Study, Study, Study…………………..