Download Minerals 1 - Brock University

ERSC 2P12 Minerals 1
Minerals
Background material essential in the
description of rocks
ERSC 2P17 - Brock University Greg Finn 2006
Minerals
• This course is not a replacement or
substitute for mineralogy (ERSC 2P21)
• how to identify and recognize minerals that
make up rocks
• in excess of 3,000 minerals have been
identified on Earth
• however 90-95% of the Earth’s crust is
composed of 8 minerals (these plus ~12
more you should be familiar with)
ERSC 2P17 - Brock University Greg Finn 2006
What is a Mineral?
• A homogeneous, naturally occurring, solid,
inorganic substance, with a definable
chemical composition, and an internal
structure characterized by an orderly
arrangement of atoms, ions and molecules
in a lattice.
ERSC 2P17 - Brock University Greg Finn 2006
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ERSC 2P12 Minerals 1
What is a Mineral?
Homogeneous
ERSC 2P17 - Brock University Greg Finn 2006
What is a Mineral?
Naturally Occurring
ERSC 2P17 - Brock University Greg Finn 2006
What is a Mineral?
Solid
ERSC 2P17 - Brock University Greg Finn 2006
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ERSC 2P12 Minerals 1
What is a Mineral?
Inorganic Substance
ERSC 2P17 - Brock University Greg Finn 2006
What is a Mineral?
Definable Chemical Composition
ERSC 2P17 - Brock University Greg Finn 2006
What is a Mineral?
Orderly Arrangement of Atoms
ERSC 2P17 - Brock University Greg Finn 2006
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ERSC 2P12 Minerals 1
Naming Minerals
• Each mineral has its own name, generally
derived from:
ERSC 2P17 - Brock University Greg Finn 2006
Naming Minerals (continued)
ERSC 2P17 - Brock University Greg Finn 2006
Groups of Minerals
• Different groups of minerals which are
important to humans:
ERSC 2P17 - Brock University Greg Finn 2006
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ERSC 2P12 Minerals 1
Classes of Minerals
• >3,000 minerals have been identified
• can be separated into 7 groups or classes
based on the chemical similarities and
differences
• silicates vs nonsilicates
ERSC 2P17 - Brock University Greg Finn 2006
Classes of Minerals
• Silicates comprise most of the minerals
found on Earth
• basic building block is the silica tetrahedron
consisting of one silicon atom surrounded
by 4 oxygen atoms
• large number of silicate minerals identified
and these differ in the way the silica
tetrahedra are linked and the cations present
ERSC 2P17 - Brock University Greg Finn 2006
Silica Tetrahedron
• 4 oxygen surrounding
1 silicon
Exploded view
Schematic view
ERSC 2P17 - Brock University Greg Finn 2006
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ERSC 2P12 Minerals 1
Nonsilicates
• Oxides
• Sulphides
• Sulfate
ERSC 2P17 - Brock University Greg Finn 2006
Nonsilicates
• Halides
• Carbonates
• Native elements
ERSC 2P17 - Brock University Greg Finn 2006
Isolated/Independent Silicates
• Si:O 1:4
ERSC 2P17 - Brock University Greg Finn 2006
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ERSC 2P12 Minerals 1
Chain Silicates
• Single-chain
• Double-chain
– Si:O 1:3
– Si:O 4:11
ERSC 2P17 - Brock University Greg Finn 2006
Phyllosilicates
• Sheet silicates
– Si:O 2:5
ERSC 2P17 - Brock University Greg Finn 2006
Tectosilicates
Structure too
complicated to
show
• Framework Silicates
– Si:O 1:2
ERSC 2P17 - Brock University Greg Finn 2006
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