Properties of Minerals - Earth and Life Science

This presentation explores the key properties that define minerals, crucial components of Earth's crust. It covers the fundamental characteristics used to identify and classify minerals, such as hardness, luster, color, streak, cleavage, fracture, and specific gravity. The presentation also discusses how these properties relate to the mineral's internal structure and composition.

1. Minerals

2. A.What is a mineral?
Mineral Characteristics
shared by all minerals:
1. Natural
–occurs naturally
–NOT manmade

3. What is a mineral?
1. Natural
2. Inorganic
–Is not alive
–Was never alive

4. What is a mineral?
1. Natural
2. Inorganic
3. Crystalline
–Atoms are arranged
in an orderly pattern

5. What is a mineral?
1. Natural
2. Inorganic
3. Crystalline
4. Definite chemical
composition
–Chemical formula
–SiO
2 is Quartz

6. What is a mineral?
1. Natural
2. Inorganic
3. Crystalline
4. Definite chemical composition
5. Solid
–Not a gas, not a liquid

7. How will we remember this?
Natural
Inorganic
Crystalline
Definite chemical composition
Solid

8. Mineral Characteristics shared
by all minerals:
Now I Can Define mineralS!
Natural
Inorganic
Crystalline
Definite chemical composition
Solid

9. B. Physical Properties of Minerals
1. Color
–First impression
–Not very reliable because lots of minerals
can occur in many different colors

10. Quartz
Purple Amethyst

11. Fluorite
•Clear
•Blue
•Green
•Purple

12. Physical Properties of Minerals
1. Color
2. Streak
–The TRUE color of a mineral
–Color of a mineral’s powder

13. Streak
Minerals with a hardness greater than “7” usually
don’t create a streak on the streak plate because
they are harder than the Porcelain tile (unless the
streak plate is specially made).

14. Physical Properties of Minerals
1. Color
2. Streak
3. Hardness
–A mineral’s resistance to being scratched
–Mohs Hardness Scale from 1-10
Hardness depends on how “tightly
packed” the atoms are

15. Mohs Hardness Scale
1Talc
2Gypsum
3Calcite
4Fluorite
5Apatite
6Potassium feldspar
7Quartz
8Topaz
9Corundum
10Diamond Hardest
Softest

17. Physical Properties of Minerals
1. Color
2. Streak
3. Hardness
4. Cleavage
–Splits along
definite planes

18. “Cleav” = to split
Cleaver

20. Physical Properties of Minerals
1. Color
2. Streak
3. Hardness
4. Cleavage
5. Fracture
–Breaks irregularly,
jagged edges

21. Fracture

22. Physical Properties of Minerals
1. Color
2. Streak
3. Hardness
4. Cleavage
5. Fracture
6. Luster
–How light shines off a mineral
–Metallic or Nonmetallic

23. Luster
Metallic Nonmetallic

24. Physical Properties of Minerals:
Used for Identification (I.D.)
Color
Streak
Hardness
Cleavage
Fracture
Luster

25. C. Special Properties
1. Magnetism
–Attracted to a
magnet
–Contains IRON,
cobalt, or nickel

26. Special Properties
1. Magnetism
2. Double refraction
–Looking through it, you see “double”
–Ex. Calcite

27. Special Properties
1. Magnetism
2. Double refraction
3. Fluorescence
–Glows under ultraviolet (UV) light

28. Fluorescence
under ultraviolet,
UV light

29. Special Properties
1. Magnetism
2. Double refraction
3. Fluorescence
4. Phosphorescence
–Continues to glow even after the
UV light has been removed

30. Special Properties
1. Magnetism
2. Double refraction
3. Fluorescence
4. Phosphorescence
5. Piezoelectric
–Electricity is generated from Pressure
–Example: Quartz

31. Piezoelectric (Pressure=Electricity)

32. Special Properties
Magnetism
Double refraction
Fluorescence
Phosphorescence
Piezoelectric

33. D. Identification Tests
1. Hardness
2. Streak (True Color)
3. Acid Test
–Use hydrochloric acid
–Tests for carbonate (calcite)

34. Caves can form in rocks with
calcite, like here in Harrisonburg!
Acid in
groundwater
dissolves the
calcite