Introduction to Minerals
Minerals and Rocks?
• What is the difference between a rock and a
mineral?
• (write the correct response for your notes)
• Most rocks are made of one or more
minerals. Minerals are made out of individual
elements. A mineral is no a rock. It goes:
• Elements=minerals=rocks.
Minerals
• Minerals DEFINED:
• A mineral is a naturally occurring, inorganic,
solid substance with a definite chemical
composition and structure.
• Can be identified based on CHEMICAL and
PHYSICAL properties
Minerals Overview
• How many minerals are there?
• There are well over 4,000 officially recognized mineral species and
as many as a hundred new ones are described each year.
• Why are minerals important?
• Minerals, as the constituents of rocks, make up the solid earth on
which we live. Minerals exposed on and near the Earth's surface
provide essential nutrients and conditions for plant and animal
life. Minerals have supported and been controlling influences on
the development of and interactions between societies and
civilizations throughout human history. Many wars and conquests
have occurred because of the quest for mineral resources and the
ages of ancient human civilization are actually defined by Man’s use
of mineral materials
What are the major mineral forming
elements found in Earths Crust?
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4 most common elements in Earths crust
Oxygen
Silicon
Aluminum
Iron
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Most minerals are made up of different variations of these 4 elements. These
minerals can be broken into 3 groups
Silicates
Carbonates
Oxides
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SILICATE GROUP
• Most abundant type of minerals on Earth
• Silicates make up approximately 96% of Earth
minerals
• Made primarily of Silicon and Oxygen
• Most common types of Silicates:
• Quartz
• Feldspar
CARBONATE GROUP
• Carbonates are minerals composed of one or
more metallic elements with the compound
CO3.
• Primary examples of carbonates are Calcite
and dolomite.
• Carbonates make up common rocks such as
limestone, coquina, and marble.
OXIDE GROUP
• Oxide’s are compounds of oxygen and some
type of a metal.
• AN EXAMPLE: IRON OXIDE
• Pittsburghanese—errrn oxide
IDENTIFYING & CHARACTERIZING
MINERALS
There are 4 MAIN ways to Identify minerals
COLOR
STREAK
LUSTER
HARDNESSS
COLOR
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Color- most noticeable feature of any mineral.
The color of a mineral is caused by the trace elements present in the mineral
One type of mineral can be different colors based on what type of trace elements
are present in the mineral
• EXAMPLE: QUARTZ
STREAK
• Streak: The color of a mineral when it is broken up and
powdered down.
• The streak of a mineral does not always match the minerals
external color.
LUSTER
• Luster- The way that a mineral reflects light
from its surface.
• Luster is either described as metallic or non
metallic
LUSTER
OR
METALLIC
NON-METALLIC
METALLIC
NON METALLIC
HARDNESS
• HARDNESS- measure of how easily a mineral
can be scratched
• Hardness is determined by the arrangement
and chemical structure of the individual
atoms in a mineral.
• MOHS HARDNESS SCALE is used to determine
the hardness of an unknown mineral, in
comparison to easily recognized minerals
Atomic arrangement of elements in a
mineral
Minerals can also be identified by looking at
features such as cleavage and fracture
Cleavage: A mineral that splits relatively easy
and evenly among one or more flat planes.
Atomic arrangement of elements in a
mineral
• Fracture: When a mineral breaks unevenly with rough and
jagged edges
• Think of minerals like this:
• A house built with a good structure will not fall apart as
easily, A house poorly built has a better chance of falling
apart. The structure of a mineral and how well it is built
with its atoms determine its cleavage and fracture type
• Talc (softest mineral that exists): poorly built house
• Diamond (hardest mineral that exists) Well built house