1. Minerals

2. ESRT Mineral Chart Click Here
Key Concept #1
What is a mineral?
naturally occurring
inorganic
A mineral is a
definite chemical composition
substance which has a
What would be the opposite of this?
man-made
organic
random composition
ESRT Mineral Chart Click Here

3. The reason why minerals have different physical properties is due to
Key Concept #2
The reason why minerals have
different physical properties is due to
their internal arrangement of atoms

4. An example of two minerals which have
Key Concept #2
An example of two minerals which have
the same chemical composition but different
physical properties is
Click Here
graphite & diamond

5. The Main Physical Properties Used to Identify Minerals
Key Concept #3
The Main Physical Properties
Used to Identify Minerals
A. Color
1. a poor indicator
a. minerals can be multiple colors
b. many minerals are the same color

6. One Mineral,
Many Colors

7. Different Minerals
Same Color

8. The Main Physical Properties Used to Identify Minerals
Key Concept #3
The Main Physical Properties
Used to Identify Minerals
B. Streak
more reliable than color
the powder form of a mineral

9. The Main Physical Properties Used to Identify Minerals
Key Concept #3
The Main Physical Properties
Used to Identify Minerals
C. Luster
how light reflects off a mineral
a. metallic
b. non-metallic
-looks like a metal
-Leaves a dark (black, grey, green or brown) streak on a white streak plate
-looks earthy, waxy,
greasy or brilliant
-leaves white or no streak on a black streak plate

10. Key Concept #3 The Main Physical Properties Used to Identify Minerals
D. Cleavage
-mineral breaks in a predictable pattern
because of its arrangement of atoms
-At least one distinct flat side when broken

11. Examples of Cleavage

12. Examples of Cleavage

13. Examples of Cleavage

14. Examples of Cleavage

15. Examples of Cleavage

16. Examples of Cleavage

17. Examples of Cleavage

18. Key Concept #3 The Main Physical Properties Used to Identify Minerals
E. Fracture
-the mineral breaks randomly
-Irregular sides

19. Key Concept #3 The Main Physical Properties Used to Identify Minerals
F. Hardness
1. resistance to being scratched- something softer than a material cannot scratch the harder material
2. It is NOT the same as breaking!
For example:
You can break glass easily with steel.
However, steel will not scratch glass.

20. The Main Physical Properties Used to Identify Minerals
Key Concept #3
The Main Physical Properties
Used to Identify Minerals
Hardness
MOH’S SCALE OF HARDNESS
Hardness
Mineral
1 (softest) 6 2 7 3 8 4 9 5
10 (hardest)
TALC
ORTHOCLASE
GYPSUM
QUARTZ
CALCITE
TOPAZ
FLUORITE
CORUNDUM
APATITE
DIAMOND

21. oxygen silicon Key Concept #4
Minerals have a definite chemical composition.
The two elements by mass that make up the greatest
percentage of the Earth’s crust are
oxygen
silicon

22. silicates (SiO4) Key Concept #4
Minerals have a definite chemical composition.
These two elements combine to form compounds called
silicates (SiO4)

23. silicon-oxygen tetrahedra
Key Concept #4
Minerals have a definite chemical composition.
They combine in a specific structure called a:
silicon-oxygen tetrahedra

24. REVIEW- WHAT IS A MINERAL?
A mineral is naturally occurring, inorganic, and crystalline solid having a definite chemical composition
Each mineral has its own distinctive crystal structure that can lead to a very accurate ID
All minerals are solids that are composed of one or more chemical elements

25. All minerals are rocks, but not all rocks are minerals nor are they all composed of minerals- the main reason: rocks can be organic like coal
Minerals form as the result of inorganic crystallization or by the re-crystallization of atoms in various rock-forming environments

26. Minerals can be identified by color, streak, luster, hardness, density, cleavage, crystal structure and other characteristics (ex. magnetism, response to hydrochloric acid, etc)