Minerals
Chap. 4
• What are Minerals?
• Identifying Minerals
Which of these are minerals?
AMBER
COAL
MICA
PEARL
SUGAR
QUARTZ
HALITE
How many types of minerals do
you think there are in the earth’s
crust?
How many types of minerals do
you think there are in the earth’s
crust?
About 3000,
but only 30 minerals are common.
What are minerals? – 4.1
Objectives
• Define a mineral
• Describe how
minerals form.
• Identify the most
common elements in
Earth’s crust.
I. Mineral
Mineral
Naturally occurring,
inorganic solid with a
specific chemical
composition and definite
crystalline structure
I. Mineral
A. Naturally occurring,
inorganic
I. Mineral
A. Naturally occurring,
inorganic
B. Solids with specific
compositions
I. Mineral
A. Naturally occurring,
inorganic
B. Solids with specific
compositions
C. Definite crystalline
structure
Crystal Systems
Tetragonal
Cubic
Orthorhombic
Hexagonal
Triclinic
Monoclinic
I. Mineral
II. Mineral formation
A. Some from magma
I. Mineral
II. Mineral formation
A. Some from magma
B. Some from solutions
III. Mineral Groups
III. Mineral Groups
A. Silicates
Silicates
- Made of silicon and oxygen
Silicates
- Made of silicon and oxygen
- Make up about 96% of minerals
found in earth’s crust
Silicates
- Made of silicon and oxygen
- Make up about 96% of minerals
found in earth’s crust
- Include feldspar and quartz.
III. Mineral Groups
A. Silicates
B. Carbonates
Carbonates
- Made of metal bonded to
carbonate, CO32-
Carbonates
- Made of metal bonded to
carbonate, CO32- Found in limestone, malachite
and marble
III. Mineral Groups
A. Silicates
B. Carbonates
C. Oxides
Oxides
- Made of metal bonded to oxygen
Oxides
- Made of metal bonded to oxygen
- Hematite Fe2O3 and magnetite
Fe3O4 are common iron oxide
minerals
III. Mineral Groups
A. Silicates
B. Carbonates
C. Oxides
D. Halides
III. Mineral Groups
A. Silicates
B. Carbonates
C. Oxides
D. Halides
E. Native Elements
III. Mineral Groups
A. Silicates
B. Carbonates
C. Oxides
D. Halides
E. Native Elements
F. Sulfates
The End
Identifying Minerals 4.2
Objectives
• Classify minerals
according to their
physical and chemical
properties
• Identify different
types of minerals
• Discuss how minerals
are used
I. Mineral Identification
I. Mineral Identification
azurite
A. Color
rhodochrosite
malachite
turquoise
I. Mineral Identification
A. Color
B. Luster (shininess)
Luster is the way the mineral
surface reflects light.
I. Mineral Identification
A. Color
B. Luster (shininess)
1. metallic
pyrite
galena
I. Mineral Identification
A. Color
B. Luster (shininess)
1. metallic
2. non-metallic
olivine
feldspar
I. Mineral Identification
A. Color
B. Luster
C. Texture
Texture is how a mineral feels
to the touch.
I. Mineral Identification
A. Color
B. Luster
C. Texture
Talc:
feels greasy
fluorite:
feels smooth
I. Mineral Identification
A.
B.
C.
D.
Color
Luster
Texture
Streak
Streak is the color of the powder of
the mineral.
I. Mineral Identification
A.
B.
C.
D.
Color
Luster
Texture
Streak
Hematite:
Reddish
brown streak
Pyrite:
Dark grayblack streak
I. Mineral Identification
A.
B.
C.
D.
E.
Color
Luster
Texture
Streak
Hardness
Hardness is a measure of how
easily a mineral is scratched.
I. Mineral Identification
F. Cleavage and Fracture
Cleavage means a mineral
splits easily and evenly along
one or more flat planes.
Fracture means a mineral breaks
with jagged, rough edges
Cleavage or Fracture?
Mica: exhibits basal cleavage
Cleavage or Fracture?
Halite: exhibits cubic cleavage
Cleavage or Fracture?
Obsidian: exhibits fracture
I. Mineral Identification
F. Cleavage and Fracture
G. Density and Specific
Gravity
Density is a measure of the mass
per unit of volume.
I. Mineral Identification
F. Cleavage and Fracture
G. Density and Specific
Gravity
H. Other properties
I. Mineral Identification
F. Cleavage and Fracture
G. Density and Specific
Gravity
H. Other properties
1. refraction
Refraction means the bending of
light
I. Mineral Identification
F. Cleavage and Fracture
G. Density and Specific
Gravity
H. Other properties
1. refraction
2. reacting with HCl
II.Other terms
II.Other terms
A. Ores
A material for which it is profitable
to mine
II.Other terms
A. Ores
B. Gems
Valuable minerals prized for rarity
and beauty
The End