Transcript Minerals
Minerals
Chapter 3
Minerals – naturally occurring, inorganic solid
with a definite structure and composition
Over 4000 minerals
5 Characteristics of Minerals:
1.
2.
3.
4.
5.
formed by natural processes – salt, diamonds
Inorganic – no Carbon
Solids
Unique chemical composition
repeated pattern
Crystals – solid with atoms are arranged in
repeating patterns
Minerals formed:
1. from magma – cooling of hot melted rock
2. liquid evaporating - crystals
Silicates – minerals that contain silicon and oxygen
and usually one or more other elements
Silicon and Oxygen the two most abundant elements
in earths crust
Mineral Identification
1. Physical Properties –
Color
Appearance
Hardness – Mohr hardness scale
Luster – how light is reflected
Metallic or non metallic
Streak – color of the mineral when it is broken up and
powdered
Cleavage and fracture – how it breaks
Cleavage – breaks along smooth flat surfaces Mica
Fracture – rough, jagged edge - Quartz
Luster – how light is reflected
Metallic or non metallic
Streak – color of the mineral when
it is broken up and powdered
Hardness
3.2 How Minerals Form
In crystallization the atoms are arranged
either by:
1. Magma and Lava
Hot magma cools inside the earth
Lava (magma on the surface) hardens on the
surface
Both form crystals when they cool to a
solid
2. Solution
Elements and compounds dissolved in water
leave a solution they form crystals
Minerals form by evaporation
Salt, halite, gypsum, calcite
Minerals from Hot Water Solutions
Elements and compounds dissolve
Vein – narrow channel or slap of a mineral
different from the surrounding rock
3.3 Mineral Resources
Uses of Minerals:
1. Gemstones – hard, colorful, mineral with a
glassy luster
2. Metals – aluminum, iron, copper or silver
3. Misc: Talc for talcum powder
Calcite for optical instruments like
microscopes
Quartz for class and electronics
Gypsum - wallboard and cement
4. Ore
– rock that contains a useful
mineral that can be sold for profit